This was CNBC's live coverage of the 2024 presidential debate between Democratic Vice President Kamala Harris and Republican former President Donald Trump in Philadelphia on Sept. 10.

Republican presidential nominee Donald Trump and Vice President Kamala Harris, the Democratic nominee, squared off in a prime-time debate in Philadelphia that may have altered the course of an already unprecedented race for the White House.

The two candidates quickly launched into a bitter, fast-moving, energized and occasionally angry back-and-forth. Trump soon appeared to veer off script, insulting Harris and repeating false conspiracies about immigrants who eat dogs.

Moments after the debate ended, superstar Taylor Swift endorsed Harris. "I'm voting for @kamalaharris because she fights for the rights and causes I believe need a warrior to champion them," Swift told her more than 280 million followers on Instagram.

"I think she is a steady-handed, gifted leader and I believe we can accomplish so much more in this country if we are led by calm and not chaos," said Swift.

Going into the debate, polling averages indicated the race was effectively tied at the national level, while surveys of the key battleground states showed Trump and Harris within a few points of each other, well within the polls' margins of error.

The coming days may see a bump for Harris after a debate performance that both Republicans and Democrats largely agreed had been excellent.

Harris' running mate, Minnesota Gov. Tim Walz, and Trump's running mate, Sen. JD Vance of Ohio, are scheduled to debate once, on Oct. 1, in New York City, hosted by CBS News.

Republicans on Trump's debate performance: 'Unprepared' and 'disaster'

Republican former New Jersey governor Chris Christie thinks Trump's debate-prep team "should be fired."

Harris "was exquisitely well prepared, she laid traps and he chased every rabbit down every hole, instead of talking about the things that he should've been talking about,' Christie told ABC News after the debate. "This is the difference between someone who's well prepared and someone who's unprepared."

Christie said Trump "spent more time talking about people eating pets," than the economy and that if he doesn't get to work he might lose the election to Harris.

Republican Sen. Lindsey Graham echoed the sentiment calling the debate a "disaster", telling MSNBC that he thought Trump was unprepared and that his debate team should be fired.

– Ece Yildirim

Harris: 'Today was a good day'

Harris rallied supporters at a watch party following her debate against Trump, saying it was a "good day."

"Today was a good day. We gotta work tomorrow. We got 56 days to go, we got a lot of work to do," Harris told the audience. "And let me just say that I think we all know that tonight was a night that highlights something that you all have been working so hard on."

The Democratic nominee thanked the room for their support and campaign efforts in the key battleground of Pennsylvania, emphasizing the tightness of the race nationally.

"We have 56 days to go, and guys, we're still the underdogs in this race. It's tight," Harris said.

Harris walked off the stage to the tune of "The Man" by Taylor Swift, who endorsed Harris moments after the debate concluded.

– Josephine Rozzelle

Harris challenges Trump to a second debate

Just moments after the two candidates left the debate stage, the Harris campaign challenged Trump to a second debate.

"Under the bright lights, the American people got to see the choice they will face this fall at the ballot box: between moving forward with Kamala Harris, or going backwards with Trump," Campaign Chair Jen O'Malley Dillon said in a statement.

"That's what they saw tonight and what they should see at a second debate in October. Vice President Harris is ready for a second debate. Is Donald Trump?"

– Josephine Rozzelle

Trump attacks debate moderators, claims victory

Minutes after the debate, Trump claimed on Truth Social that "people are saying" he won "BIG."

In a follow-up post, Trump lashed out at the moderators.

"I thought that was my best Debate, EVER, especially since it was THREE ON ONE!" he wrote.

He also thanked Fox News host Jesse Watters for his "nice words" and re-posted a flattering statement from House Republican leader Elise Stefanik of New York, one of his most loyal supporters.

— Kevin Breuninger

Taylor Swift endorses Harris, signs message as 'Childless Cat Lady'

Taylor Swift has endorsed Harris in an Instagram post, minutes after the debate's end.

"Like many of you, I watched the debate tonight," the pop star wrote. "I will be casting my vote for Kamala Harris and Tim Walz in the 2024 Presidential Election."

Swift signed the message with her name, followed by the title "Childless Cat Lady," a reference to JD Vance's now-famous insult toward Democratic women, which he has faced backlash for.

In the endorsement, Swift also mentioned false AI impersonations of herself endorsing Trump, which she said made her worried about misinformation.

"It brought me to the conclusion that I need to be very transparent about my actual plans for this election as a voter," Swift said.

Read the full story here.

— Rebecca Picciotto

Trump and Harris walk off stage without shaking hands

The debate, which started on a relatively cordial note with Trump and Harris shaking hands, ended with each nominee silently walking off stage in opposite directions.

— Kevin Breuninger

Role reversal: Harris speaks more than Trump in second half of debate

Harris spoke for 12.5 minutes during the second segment of tonight's debate. Trump spoke for 11.3 minutes.

The former president spoke five more times than Harris did between the two ad breaks.

– Josephine Rozzelle

Harris donors are 71% women in first debate hour, campaign says

In the first hour of the debate starting at 9 p.m. ET, Harris donors were 71% women, a Harris campaign official says in an email to CNBC.

During that first hour, Harris called Trump's stances on IVF and abortion access "insulting to the women of America."

— Brian Schwartz & Rebecca Picciotto

Democrats raised over $6 million in final hour of debate

Democrats raised over $6 million in the second hour of the debate between Trump and Harris, according to a tracker of ActBlue's live online ticker.

ActBlue, which process online contributions to Democrats and groups aligned with the party, raised the amount as Trump and Harris sparred over a variety of issues, including taxes, the border and energy policy.

The tracker shows ActBlue processed just over $1 million during the first hour of the debate.

- Brian Schwartz

Trump says he has 'concepts' of health care reform plan — give no specifics

Trump said he has "concepts" of a health care reform "plan," but offered no specifics — just as he has done for years when pressed on what he would want to replace Obamacare, or the Affordable Care Act.

"I have concepts of a plan," Trump said. "I'm not President right now, but if we come up with something, I would only change it if we come up with something that's better and less expensive."

"And there are concepts and options we have to do that, and you'll be hearing about it in the not-too-distant future," Trump said.

- Dan Mangan

Trump and Harris spar on Israel, Harris calls for two-state solution

Harris called for a ceasefire in the Gaza strip, while underlining her support for Israel's "right to defend itself."

Harris said she supports a "two-state solution where we can rebuild Gaza, where the Palestinians have security, self-determination and the dignity they still rightly deserve."

Trump clapped back, claiming that Harris hates both Israel and the Arab population simultaneously.

"If she's president, I believe that Israel will not exist within two years from now, and I've been pretty good at predictions, and I hope I'm wrong about that one," Trump said.

Trump has previously called himself "the best friend that Israel, and the Jewish people, ever had," on his Truth Social account. But he has also directed antisemitic attacks at Pennsylvania governor Josh Shapiro and Harris' husband Doug Emhoff, who are both Jewish and both Democrats.

Although Harris has taken a more critical approach towards Israeli Prime Minister Benjamin Netanyahu's and the humanitarian crisis in Gaza than President Biden, she has time and again continued to express "ironclad support" for Israel.

Harris has said that she and President Biden are working to get a ceasefire and hostage deal done but a deal is in stagnation as the war continues to escalate.

— Ece Yildirim

Trump leads Harris in total speaking time so far

Trump spoke for 28.6 minutes during the first half of the debate, six minutes more than Harris, who spoke for 22.8 minutes.

The former president spoke 26 times before the ad break, while Harris spoke 15 times.

– Josephine Rozzelle

Harris tells Trump: 'You're not running against Joe Biden, you're running against me'

Trump has repeatedly mentioned Biden during the debate, and Harris finally tried to use it to her advantage.

"Well, first of all, it's important to remind the former president: You're not running against Joe Biden, you're running against me," Harris said.

- Dan Mangan

Harris punctures Trump's ego: He was 'fired by 81 million people'

Harris just went after Trump's ego, hard.

After Trump repeated false conspiracy claims about his 2020 election loss, Harris said, "Donald Trump was fired by 81 million people."

"Clearly he is having a very difficult time processing that," she quipped.

She went on, "I'm going to tell you that I have traveled the world as vice president of the United States and world leaders are laughing at Donald Trump."

"I have talked with military leaders, some of whom worked with you, and they say you're a disgrace," she continued.

Trump's denials about his election loss, and his many attempts to challenge that loss in court, "leads one to believe that perhaps we do not have, in the candidate to my right, the temperament" to see the truth clearly, she said.

— Kevin Breuninger

Here are the candidates' border policy proposals

Trump has vowed to carry out "mass deportations" of illegal immigrants if he returns to the White House. The 2024 Republican platform also promises to complete the border wall, a hallmark of Trump's first term, send more law enforcement officers to the southern border and increase penalties for illegal immigrants.

On the Democratic side, Harris — who touts her experience as a prosecutor of a border state — has promised to revive the bipartisan border security bill that Senate Republicans blocked in May. 

The Biden-backed bill was aimed at cracking down on border crossing and would have raised the qualification requirements for asylum. It would have also given the president the power to close the border if immigration surpassed a certain level.

– Josephine Rozzelle

Harris seizes opportunity to needle Trump over criminal cases

Harris took direct aim at Trump's criminal cases during their heated debate.

 "This is so rich coming from someone who has been prosecuted for national security crimes, economic crimes, election interference, has been found liable for sexual assault and his next big court appearance is in November at his own criminal sentencing," Harris said.

Trump then tried to falsely suggest that his recent slate of legal cases were meant to target him by his political opponents.

"Excuse me. Every one of those cases was started by them against their political opponent."

- Brian Schwartz

Trump repeats false immigration conspiracies: 'They're eating the dogs'

Trump harped on a false conspiracy about immigrants stealing and eating people's pets, repeating the same claim his running mate JD Vance has faced backlash for in recent days.

"In Springfield, they're eating the dogs, the people that came in, they're eating the cats. They're eating the pets of the people that live there," Trump said.

ABC News' David Muir tried to correct the former president, citing a Springfield, Ohio city official who told him there had been "no credible reports of specific claims of pets being harmed, injured or abused by individuals within the immigrant community."

But Trump backed his claim by pointing to television interviews he had watched: "People on television say my dog was taken and used for food."

— Rebecca Picciotto

Harris baits Trump on rallies, and he bites

Harris baited Trump with a jibe about his beloved campaign rallies, and he bit on it hard after she taunted him by saying people walked out of them before they were finished.

"I'm going to actually do something really unusual, and I'm going to invite you to attend one of Donald Trump's rallies, because it's a really interesting thing to watch," Harris said. "You will see during the course of his rallies, he talks about fictional characters like Hannibal Lecter. He will talk about windmills cause cancer."

"And what you will also notice is that people start leaving his rallies early out of exhaustion and boredom," Harris said. "And I will tell you, the one thing you will not hear him talk about is you."

Trump was annoyed by that crack, and insisted on responding to it even though he was being asked another question.

"Let me respond ... to the rallies," Trump said. "She said, people started leaving. People don't go to her rallies. There's no reason to go. And the people that do go, she's busing them in and paying them to be there and then showing them in a different light."

- Dan Mangan

Trump contradicts running mate JD Vance on national abortion ban

Trump declined to say if he would veto a national abortion ban if such a bill crossed his desk as president.

"I won't have to," he said, suggesting that bill would never pass.

A moderator followed up that Trump's running mate, Sen. JD Vance of Ohio, has said Trump would veto that bill.

"Well, I didn't discuss it with JD," Trump replied, adding, "I don't mind if he has a certain view."

— Kevin Breuninger

Trump defends tariffs at debate with Harris

Trump defended his plans to enact tariffs on imports from other countries during the debate with Harris.

"We're doing tariffs on other countries. Other countries are going to finally, after 75 years, pay us back," Trump said. "The tariff will be substantial in some cases."

He doubled down on his tariff policy proposals later in the debate.

- Brian Schwartz

'What we have done is clean up Donald Trump's mess': Harris

Harris hammered Trump on what he left the United States and the Biden administration to deal with when he exited the White House in January 2021.

"I would love to let's talk about what Donald Trump left us," Harris said.

"Donald Trump left us the worst unemployment since the Great Depression. Donald Trump left us the worst public health epidemic in a century," she continued.

"Donald Trump left us the worst attack on our democracy since the Civil War."

"And what we have done is clean up Donald Trump's mess," Harris concluded.

- Dan Mangan

Trump and Harris take the stage, shake hands

Trump and Harris took the debate stage in Philadelphia.

Unlike at Trump's last debate with Biden, the two nominees shook hands before taking their places at opposite lecterns.

— Kevin Breuninger

Pro-Palestinian protestors block off intersection near debate venue

Hundreds of pro-Palestinian protestors are blocking off the intersection of North 12th and Market Streets, NBC News reports. This is several blocks from the National Constitution Center, where the debate is being held tonight.

— Ece Yildirim

Coinbase funded group lobbies ABC News to ask a crypto question

The Stand With Crypto Alliance launched by Coinbase last year is pushing ABC News to get a crypto question asked at the debate.

The crypto lobby group initiated a letter writing petition five days ago to pressure the network to ask such a question.

In recent months, Trump has branded himself as the pro-crypto candidate. Harris hasn't yet made her official stance known on digital assets, but the Biden administration's aggressive crackdown on the industry has created an opening for the former president.

ABC didn't immediately respond to a request for comment.

- MacKenzie Sigalos

Harris spoke with Hillary Clinton ahead of tonight's debate

Harris has spoken with former Sec. of State Hillary Clinton about tonight's debate, three sources familiar with their discussions told NBC News.

Clinton, the 2016 Democratic nominee and the only other woman to have faced Trump in a one-on-one debate, advised Harris that Trump might attempt to "bait" her, and suggested Harris provoke Trump directly.

Philippe Reines, Clinton's former aide, has played the role of Trump in Harris' debate prep — reprising the role he played for Clinton eight years ago.

– Josephine Rozzelle

Shapiro, Newsom, Cooper among Harris allies in the spin room post-debate

No matter how the tonight's debate goes, the Harris campaign is stocking a room full of surrogates to spin the outcome in her favor.

The Harris spin room will feature some higher-profile Democrats like Pennsylvania Gov. Josh Shapiro and North Carolina Gov. Roy Cooper, two names that were once floated to be Harris' running mate. California Gov. Gavin Newsom and New Mexico Gov. Michelle Lujan Grisham will also attend.

Also on the list are surrogates who can speak on election issues like abortion access and veterans' protections, along with government officials who have history with Harris.

"Some of these elected officials have worked alongside the Vice President for years," the campaign wrote in a memo. "Many of these surrogates are also uniquely qualified to speak to why Donald Trump is unfit to lead."

Here is the full list of spin room surrogates the campaign has announced:

• California Gov. Gavin Newsom
• New Mexico Gov. Michelle Lujan Grisham
• Pennsylvania Gov. Josh Shapiro
• North Carolina Gov. Roy Cooper
• Brigadier General Steve Anderson (Ret.)
• Senator Laphonza Butler
• Senator Tammy Duckworth 
• Senator Chris Murphy 
• Congressman Jason Crow
• Congresswoman Veronica Escobar
• Congressman Robert Garcia
• Congressman Ted Lieu
• Former Congressman Cedric Richmond
• Reproductive Freedom for All President & CEO Mini Timmaraju 
• Gold Star Father Khizr Khan

— Rebecca Picciotto

Trump's entourage includes Laura Loomer, Rep. Matt Gaetz

Trump emerged from his plane at 6:52 p.m. ET.

The former president, clad in his standard uniform of a navy blue suit, solid red tie and white shirt, was not accompanied by former first lady Melania Trump as he descended the aircraft staircase and entered his motorcade.

A coterie of campaign officials and other aides disembarked before him — including Laura Loomer, the pro-Trump conspiracy theorist and far-right activist.

Other passengers seen exiting the plane included Trump's son Eric Trump and his wife, Republican National Committee co-chair Lara Trump, Rep. Matt Gaetz of Florida, former Rep. Tulsi Gabbard of Hawaii and attorney Alina Habba.

— Kevin Breuninger

Trumps lands in Philadelphia

Trump's plane touched down at Philadelphia International Airport shortly before 6:40 p.m. ET.

– Josephine Rozzelle

Trump posts bizarre images of cats and ducks while flying to debate

Trump posted bizarre artificial intelligence-generated images featuring cats and ducks on social media while flying to the debate, in a nod to a false conspiracy theory that Haitian immigrants in Springfield, Ohio, were eating such animals.

One image posted by Trump on his Truth Social account showed him sitting on a plane with a white cat in his lap, with other cats and ducks next to him and in the background.

Another image he posted showed tabby cats wearing tactical gear while toting assault rifles and wearing ball caps bearing the word "MAGA" — an acronym for Trump's political slogan "Make America Great Again."

Trump's running mate Vance on Monday in a post on X wrote, "Months ago, I raised the issue of Haitian illegal immigrants draining social services and generally causing chaos all over Springfield, Ohio."

"Reports now show that people have had their pets abducted and eaten by people who shouldn't be in this country," Vance wrote.

Authorities in Springfield disputed Vance's claims. John Kirby, spokesman for the National Security Council, called the claim "yet another conspiracy theory that's just seeking to divide people based on lies, and, let's be honest, based on an element of racism,"

"This kind of language, this kind of disinformation, is, is dangerous because there will be people that believe it no matter how ludicrous and stupid it is, and they might act on that kind of information and act on it in a way where somebody could get hurt," Kirby said.

- Dan Mangan

Harris should 'offer voters hope,' not just attack Trump, Chris Christie says

If Harris wants to win over undecided voters during the debate, she has to do more than just attack Trump, Republican former New Jersey Gov. Chris Christie wrote in a New York Times op ed.

"There is an opening at the debate to offer an alternative — to offer voters hope," Christie wrote.

"Ms. Harris has a better opportunity to do this than Mr. Trump. She needs only to have the courage to do it; to break away from the political culture of petty bickering and name calling that her opponent personifies."

Christie, who ran for the Republican presidential nomination in 2016 and 2024, has debated against Trump and helped prepare him for other debates.

"No one has more experience in the arena listening to his attacks and debunking them than I have," he claimed. "That's how I know that Ms. Harris's goal during the debate cannot be merely besting Mr. Trump or out-insulting him."

Despite serving as vice president since 2021, many voters say they still don't know enough about Harris. Christie, who put himself in that group, argued that presents an opportunity for her.

"She needs to demonstrate a commitment to changing not just the way we talk to one another, but the very way we must steer our governance on a more productive path," he wrote.

"For Republicans and independents who do not support Mr. Trump, this is how she earns their vote. They want to be for something, not just against someone."

— Josephine Rozzelle

Trump tells Republicans to shut down government in order to keep voter ID bill alive

Trump's message to congressional Republicans: If their stopgap spending bill doesn't come with the GOP's hardline voter ID bill, go ahead and shut down the government.

"If Republicans in the House, and Senate, don't get absolute assurances on Election Security, THEY SHOULD, IN NO WAY, SHAPE, OR FORM, GO FORWARD WITH A CONTINUING RESOLUTION ON THE BUDGET," the Republican presidential nominee wrote in a Truth Social post.

"THE DEMOCRATS ARE TRYING TO 'STUFF' VOTER REGISTRATIONS WITH ILLEGAL ALIENS. DON'T LET IT HAPPEN – CLOSE IT DOWN!!!"

Republican House Speaker Mike Johnson is adamant about attaching the SAVE Act, which would require individuals to show proof of citizenship for voter registration, to his six-month spending resolution.

Democrats have repeatedly said they will vote against any funding bill that is paired with the SAVE Act, leaving lawmakers at a stalemate as the Sept. 30 partial shutdown deadline nears.

Read the full story here.

— Rebecca Picciotto

How RFK Jr. could help Trump win the election

Ever since suspending his campaign and endorsing Trump on Aug. 23, former independent presidential candidate RFK Jr. has fought to remove himself from swing state ballots.

The ballot plan was meant to help Trump, who often polls better in head-to-head matchups with Harris than in six-candidate races.

The only swing states where that is not true are Nevada and Georgia, where it is Harris who polls better in a two-way race, according to polling averages from RealClearPolling.

Three states — Michigan, North Carolina and Wisconsin — also rejected Kennedy's request to withdraw, leading to a legal fight in each of the battlegrounds.

On Monday, the Michigan Supreme Court ruled that Kennedy would stay on the state's ballot. Just hours later, the North Carolina Supreme Court ruled the opposite, ordering state election officials to reprint ballots without Kennedy's name.

A judge has yet to rule on Kennedy's lawsuit in Wisconsin.

— Josephine Rozzelle

Trump aides project confidence, but claim Harris has a higher bar to clear

Trump and his allies have exuded a qualified confidence ahead of the debate, boasting the Republican nominee's speaking skills while asserting that it is Harris who has more to prove.

"You can't prepare for President Trump. There's just no way to do it," Trump campaign spokesman Jason Miller said Monday in a press call previewing the debate.

"It's imagine like a boxer trying to prepare for Floyd Mayweather or Muhammad Ali. You just you don't know what angle they're going to come at you with. You don't know what style of contrast that they're going to deliver," Miller said.

Trump's recent debate record is indeed enviable. While he skipped all of the Republican presidential primary debates, his appearance against Biden in June could not possibly have gone better for him.

But Harris, 59, is unlikely to suffer the same pitfalls as the 81-year-old Biden, whose failure in that debate was a result of his own shortcomings rather than Trump's abilities. The facts of Harris' age, race and gender also make her an altogether different opponent for Trump, 78, to face.

The Trump campaign, however, said their nominee is not planning to change up his style.

"If it's the same one he had with Biden, it'll be a success," Miller said. "President Trump is going to be himself."

Rep. Matt Gaetz, R-Fla., on the call, said "I would just add the stakes are far higher for the vice president in this debate because she doesn't do interviews with all of you."

Tim Murtaugh, a former Trump 2020 campaign staffer, echoed that sentiment in an X post Tuesday morning.

"Harris' campaign has raised the stakes and placed enormous pressure on her to really perform well," Murtaugh wrote. "It's a high bar she set for herself."

Trump has projected even more confidence by claiming he will prevail in a hostile environment, while insinuating without evidence that Harris will be playing with a stacked deck.

"Even if she knows the answers and knows the questions, I don't think she'll be very good," Trump said at a news conference Friday.

— Kevin Breuninger

Trump campaign lobbies debate moderators to scrutinize Harris crime data

The Trump campaign has released a long memo that aims to draw debate moderators' attention to what it says are Harris' "preposterous claims" about crime and immigration rates.

The Trump campaign said Harris is falsely claiming that violent crime has fallen during the Biden-Harris administration. The Republican's team also asserts it is "completely false" that there are fewer illegal entries into the U.S. today than there were when Trump was in office.

The roughly 3,800-word memo to moderators David Muir and Linsey Davis of ABC News urges "media analysts" to "hold Kamala Harris to account for her egregiously false claims."

After Biden imposed an executive order in June restricting asylum to the U.S., migrant encounters at the U.S. southern border reportedly plunged. The Trump campaign memo claims that the downward trend is a mirage that masks a redirection of migrant traffic.

"Violent crime is near a 50-year low," Harris said in June. The White House has made the same claim, pointing to data from an independent police organization and crediting the American Rescue Plan for enabling public safety investment in cities. Fact checkers have backed up that claim, citing FBI statistics showing violent crime has fallen across all major categories.

The Trump campaign memo argues that other crime data, the Bureau of Justice Statistics' National Crime Victimization Survey, shows crime rising. But the most recent NCVS data ends in 2022, and the campaign memo only looks at a span from 2020 to 2022 to back its assertion of a "crime wave."

— Kevin Breuninger

Economic 'misery index' that's predicted every election winner since 1980 looking good for Harris, but it's close

A gauge of economic misery that has a strong track record of predicting elections is tilting toward a Harris victory — but it appears tight entering the race's final stretch.

You can read the full article here.

— Alex Harring

Harris wants to raise the top capital gains tax rate to 28%. How that compares to recent history

As the election ramps up, many investors are focused on capital gains taxes and how proposals from both parties could affects their assets.  

Harris last week proposed a 28% tax on long-term capital gains, or profits from the sale of assets owned for more than one year, for those making more than $1 million annually. The plan would raise the top rate from 20%.

Read the full story here.

— Kate Dore

RFK Jr. will be in the spin room for Trump tonight

Former independent presidential candidate Robert F. Kennedy Jr. will be in the spin room tonight in Philadelphia on behalf of Trump, according to Democratic National Committee spokesperson Matt Corridoni.

Kennedy suspended his campaign last month, endorsed Trump and was added to the former president's presidential transition team.

Kennedy is joining as a surrogate alongside the likes of former Democratic Rep. Tulsi Gabbard, who has been helping Trump prepare for the debate, and previous Trump challenger in the Republican primary, Vivek Ramaswamy.

— Ece Yildirim

NSC spokesman: Vance promoting false reports about Haitian immigrants is 'dangerous'

National Security Council spokesman John Kirby says it was "dangerous" for Republican vice presidential nominee Vance to share a false conspiracy theory that Haitian immigrants were stealing and eating other people's pets.

"What's deeply concerning to us is you've got now elected officials in the Republican Party pushing, you know, yet another conspiracy theory that's just seeking to divide people based on lies, and, let's be honest, based on an element of racism," Kirby tells reporters.

Vance is partially walking back his claims after local police denied the unfounded rumors about immigrants in Springfield, Ohio.

"In the last several weeks, my office has received many inquiries from actual residents of Springfield who've said their neighbors' pets or local wildlife were abducted by Haitian migrants."

"It's possible, of course, that all of these rumors will turn out to be false," Vance says.

Read the full story here.

— Josephine Rozzelle

Walz: 'Good news' is 'we know exactly what to expect' from Trump

Harris' running mate Walz said she will benefit from the fact that Trump has done so many general elections debates that the Democratic nominee will know what to expect from him.

"Let's just all be very clear — this is the most qualified person who's ready to do the job," the Minnesota governor said of Harris.

"Tonight, we'll get an opportunity to see that," Walz said. "Now, look, Donald Trump's a showman, this is his seventh general election debate. No one in modern times has done more of these."

"The good news is that this is his seventh debate, and we know exactly what to expect."

— Dan Mangan

Liz Cheney rips 'dangerous' Vance for saying he would not have certified 2020 election as VP

Former Republican Rep. Liz Cheney tore into Trump's running mate Vance, for suggesting he would have had states submit pro-Trump "alternative" electors, rather than automatically certifying the results of the 2020 presidential election.

"Let's be clear: This is illegal and unconstitutional," Cheney wrote on social media platform X in reply to Vance's remarks on the "All-In Podcast" published Monday. "The Vice President has no constitutional authority to tell states to submit alternative slates of electors because his candidate lost."

"That is tyranny," wrote Cheney, who said Friday that both she and her father, former Vice President Dick Cheney, would vote for Harris.

"Trump picked JD Vance because Vance will do whatever Trump wants, including violating the Constitution. They are both far too dangerous to serve. It's our duty to stop them," Cheney wrote.

The former congresswoman from Wyoming became Trump's most vocal conservative critic after his many attempts to overturn his loss to Biden culminated in the Jan. 6, 2021, Capitol riot.

Vance has previously made similar suggestions about how he would have handled the certification process versus then-Vice President Mike Pence, who concluded that the Constitution provides no basis for him to challenge the electoral results.

— Kevin Breuninger

Trump Media stock price surges before debate

Shares of Trump Media, the social media company majority owned by Trump, surged more than 10% in intraday trading ahead of the debate.

The positive turn for the Truth Social owner comes amid a weekslong slump that saw the company's stock crater as much as 75% from its peak in late March.

Trump Media trades on the Nasdaq as DJT, and it is widely seen as a meme stock and a barometer for Trump's political fortunes. Tuesday's gains could point to optimism among Trump Media shareholders that the debate will go well for him.

Despite posting multimillion-dollar losses and scant revenue, Trump Media still boasts a market capitalization of nearly $4 billion, making Trump's nearly 59% stake in the company worth about $2.3 billion at Tuesday's intraday price.

Trump and other company insiders will soon be free to start selling their shares. But if they do, they may tank investor confidence and drive down the company's value.

— Kevin Breuninger

The White Stripes sue Trump for using 'Seven Nation Army' without permission

Legendary duo The White Stripes sued Trump and his presidential campaign for the alleged "flagrant misappropriation" of the band's stadium-rock anthem, "Seven Nation Army."

The civil lawsuit in New York federal court was filed Monday after Trump's social media accounts posted videos of the Republican boarding a plane, backed by the hit song's iconic guitar riff.

The videos used the musical snippet to burnish Trump's public image "and generate financial and other support for his campaign and candidacy on the backs of Plaintiffs" without seeking their permission, read the lawsuit from Jack White and Meg White.

Trump should have known they would not authorize him to use the song, since they had previously publicly denounced him when a pro-Trump campaign video used the same song during the 2016 election.

The latest video has created a new association that is "even more offensive," the band alleges, because they "vehemently oppose the policies adopted and actions taken by Defendant Trump when he was President and those he has proposed for the second term he seeks."

They accuse Trump of copyright infringement, and ask that he be held liable for "significant monetary damages, attorney's fees, and costs."

The Trump campaign did not immediately respond to CNBC's request for comment.

Many other artists have demanded that Trump stop using their music.

— Kevin Breuninger

Former Trump WH officials will be Harris' guests in Philadelphia

It won't just be Harris bashing Trump in Philadelphia.

Her campaign is bringing two former Trump administration officials to the debate to warn voters about what they see as the grave threat posed by the Republican nominee, NBC News reported.

Anthony Scaramucci briefly served as Trump's communications director. Olivia Troye is a former top aide to then-Vice President Mike Pence, who also served on Trump's Covid-19 task force.

Both Scaramucci and Troye will speak to the press as Harris surrogates on Tuesday night.

Both former officials have long been vocal critics of Trump. Troye also spoke during the Democratic National Convention.

The Harris campaign is simultaneously airing a new ad on Fox News that features several other former Trump officials — including Pence, former Defense Secretary Mark Esper, former national security advisor John Bolton and former Joint Chiefs of Staff Chairman Gen. Mark Milley — criticizing him.

"Listen, don't take it from us: Take it from the ones who know Donald Trump the best and who are telling the American people exactly how unfit Trump is to serve as president," Harris campaign spokesman Michael Tyler said in a statement.

Trump will not see Scaramucci and Troye during the debate, which will take place without a live audience.

— Kevin Breuninger

CNBC's cheat sheet of U.S. economy numbers for tonight's debate watchers

When Harris and Trump take the debate stage tonight, expect an onslaught of talking points about the U.S. economy.

Both Harris and Trump have been rolling out new economic proposals and sharpening their policy platforms so that they have ample ammunition for tonight's faceoff.

As the candidates ready their attack lines, CNBC has a list of the key data about U.S. inflation, jobs, wages, deficits, GDP and more, that are likely to be raised, and fought over, later tonight.

Read the full Trump-Harris economic cheat sheet here.

— Rebecca Picciotto

Harris campaign debuts Wawa-themed billboards mocking Trump

The Harris-Walz campaign is debuting new billboards across Philadelphia ahead of tonight's debate in the city.

The billboard mocks Trump and his rally crowd sizes with a nod to the beloved local convenience store chain Wawa.

— Ece Yildirim

Obama stars in the Harris campaign's new ad, 'Crowd Size'

The Harris campaign released a new ad this morning featuring clips of former President Barack Obama's speech at the Democratic National Convention in August.

"Here's a 78-year-old billionaire who has not stopped whining about his problems," Obama says in the 30-second spot, which uses one of the most viral moments from his speech.

Among other issues, Obama drags Trump for what he says is the former president's "weird obsession with crowd sizes."

The Harris campaign says the ad, which is called "Crowd Size," is airing nationally, including on Fox News and in the West Palm Beach local media market.

While Florida is not a Democratic target this November, running the ads in Trump's backyard appears to be an attempt by the Harris campaign to provoke the former president, who watches the network on TV at his Mar-a-Lago resort.

— Josephine Rozzelle

Why Rand Paul's enthusiasm for Trump is flagging: 'I'm a deficit hawk'

Kentucky Republican Sen. Rand Paul says he supports Trump but that his concerns about the federal deficit have tempered his enthusiasm for the GOP presidential nominee.

"I think there's no question that Donald Trump is better than Kamala Harris," Paul said on CNBC's "Squawk Box."

"But as far as my enthusiasm, I'm a deficit hawk," Paul added. "The Trump administration added $8 trillion. The Biden administration is going to add $8 trillion."

Trump approved $8.8 trillion of new borrowing during his administration, but cancelled out some of it with $443 billion of deficit reduction measures, according to a report by the nonpartisan Committee for a Responsible Federal Budget.

The net total $8.4 trillion of Trump spending included roughly $3.6 trillion for Covid-19 pandemic relief and stimulus packages.

Meanwhile, Biden approved $6.2 trillion of new borrowing in his first three years and five months in office, balanced out with $1.9 trillion of deficit reduction, per the CRFB.

— Rebecca Picciotto

Where is Tim Walz today?

As his running mate counts down the hours until her debate with Trump, Tim Walz will continue campaigning in key battleground states today.

The Minnesota governor is set to speak at campaign events in Las Vegas and Phoenix on Tuesday. His last event in Pheonix is schedule to begin at 8:30 p.m. ET, a half hour before the highly anticipated debate begins.

— Josephine Rozzelle

7 in 10 Americans plan to watch the debate, NPR poll finds

Nearly three-quarters of American voters say they will watch the debate tonight, according to the latest poll by NPR, PBS News and Marist.

The debate between Trump and Biden earlier in June drew 51.3 million viewers, down from the record 73.1 million viewers who tuned in to watch the first debate between them in September 2020. That was the third-most watched debate ever, according to Statista.

— Ece Yildirim

Ohio police deny Vance claim of Haitian immigrants eating people's pets

Police in Springfield, Ohio, deny JD Vance's claim in a post on social media site X that people in the city have had their "pets abducted and eaten by people who shouldn't be in this country."

"There have been no credible reports or specific claims of pets being harmed, injured or abused by individuals within the immigrant community," the Springfield Police Department said in a statement. The police also denied that immigrants in the city had been squatting, littering or disrupting traffic.

The Vance campaign has responded with a statement of its own, saying the Ohio senator has received "a high volume of calls and emails" about an influx of Haitian immigrants in the city.

The campaign does not mention anything about pets being stolen and eaten.

— Josephine Rozzelle

Here are the rules of tonight's faceoff

Similar to the June presidential debate between Trump and Joe Biden, candidates' microphones will be muted when they are not speaking tonight, according to rules released by ABC News.

The debate will last 90 minutes with two commercial breaks, during which time Trump and Harris cannot interact with members of their staff. There is no live audience.

The nominees will have two minutes to answer each question, two minutes for rebuttal and an extra minute for follow-ups, clarifications or responses.

Trump won the coin toss and has chosen the last word. Harris has chosen to be on the right side of viewers' screens tonight. Neither of them will give an opening statement.

— Josephine Rozzelle

Trump assault accuser Jessica Leeds: He is a 'sexual predator'

Jessica Leeds, who has previously testified that Donald Trump sexually assaulted her on an airplane in the late 1970s, calls him "a sexual predator" who does not understand the "psychological damage" done to women victimized in that way.

"We cannot let this person back in the White House," Leeds, 82, said at a press conference outside of Trump Tower in Manhattan on Monday afternoon. 

Leeds spoke days after Trump lashed out at her in connection with her testimony at his trial last year for a sexual abuse and defamation lawsuit by writer E. Jean Carroll, who accused him of raping her in a New York department store in the 1990s.

Trump called Leeds' allegation that he groped her on a flight a "totally made up story," and said she "would not have been the chosen one."

On Monday, Leeds said, "He assaulted me 50 years ago and continues to assault me today."

Asked if she would sue Trump for his comments about her while denying her allegation, Leeds said, "We're considering a number of options because of his latest remarks, but no decision has been made at this time."

Carroll has sued Trump twice, and has been awarded more than $88 million in damages for defamation and sexual abuse.

— Dan Mangan

Commerce Secretary Raimondo calls Trump's tariff plan 'scary' to the private sector

Vice President Kamala Harris' ally Commerce Secretary Gina Raimondo says the debate could turn into a battle over Trump's proposed tariff policies.

"If I were a businessperson and I heard a 20% tariff on every import, and I watched [Trump] be so erratic and unpredictable — I think that's scary," Raimondo said on CNBC's "Squawk Box."

"Every businessperson deserves predictability," she added. Trump has proposed tariffs from 10% to 20% on imports from U.S. trading partners.

Harris' team has said she would "employ targeted and strategic tariffs to support American workers, strengthen our economy and hold our adversaries accountable."

— Brian Schwartz

How to watch the presidential debate

The presidential debate will be hosted by ABC News in collaboration with local affiliate WPVI-TV/6ABC.

It will air live beginning at 9 p.m. ET on ABC, and the broadcaster will be live streaming the debate on ABC News Live, Disney+ and Hulu. It will also be available on the ABC app and website, abc.com.

Other major broadcasters will simulcast the debate, including NBC, CNN, CBS and Fox News.

— Ece Yildirim