Dave McCormick, who trails Mehmet Oz by 902 votes in the Republican primary for U.S. Senate in Pennsylvania, faces long odds in passing Oz if history is any indication.
The Pennsylvania secretary of state announced Wednesday that all 67 counties must recount the ballots cast in the May 17 primary involving McCormick and Oz because the election results show the two are separated by less than 0.1% of the more than 1.3 million votes cast.
That's well within the 0.5% threshold by which Pennsylvania election code requires a recount of all the votes.
"This automatic recount is intended to ensure that the count is accurate and that there is confidences in the results and outcome," Pennsylvania Secretary of State Leigh Chapman said. "I thank everyone for their patience as we count every vote."
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Chapman said the counties will have from May 27 to June 7 to recount the votes in the Senate race. Counties must report their results by 12 p.m., June 8.
But despite the razor-thin margin separating Oz and McCormick, a national study of elections from 2000 to 2019 found only three instances in which the leader was overtaken by the second-place candidate. In each of those elections, the initial margin separating the candidates was much closer than the margin separating the candidates in the Republican primary this month.
"It is common to expect some votes to shift when you do a hand recount. In this case, the candidates are separated by about 1,000 votes and in this case, we should expect a shift of about 100 votes," Deb Otis of FairVote said in an interview Wednesday. "It is possible, but certainly an uphill battle for David McCormick."
Otis, who is senior research analyst at the nonpartisan organization, FairVote, is the author of a 2020 study that looked at the previous 20 years of statewide elections across the United States.
Only 31 times did a statewide race go to a recount. Of those, three saw the initial leader give up the advantage and lose the election, Otis said. Each had initial margins of less than 0.05%, her study found.
The difference between Oz and McCormick is about 0.09%.
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None of the three had a shift in votes from one candidate to another of more than 225 votes, according to the FairVote study.
In Pennsylvania, there have been seven recounts held since the start of the century, Chapman, the state secretary, said on Tuesday. Only one of those seven was a statewide race. In 2009, an election for state Superior Court went to a recount. The results were not reversed after the recount.
The eventual winner in the Senate race will face Democratic nominee John Fetterman in the November general election.