Why AP called the Pennsylvania Senate race for David McCormick

WASHINGTON -- Republican David McCormick cut into Democratic Sen. Bob Casey's support in Philadelphia and its populous suburbs and built leads in the more GOP-leaning parts of the state, foreclosing the incumbent's pathway to victory when The Associated Press called the race Thursday.

McCormick was leading by more than 30,000 votes when AP called the race at 4:09 p.m., and though there were an estimated 91,000 votes still outstanding at that time, there were not enough in areas supporting Casey for him to make up the difference.

McCormick didn't win in the Democratic-leaning city of Philadelphia. But like Republicans across the map and President-elect Donald Trump, he sliced significantly the support that Democrats got. For instance: Casey was winning the city with about 78% of the vote, but that was down 8 percentage points from six years ago.

McCormick was winning outright in every region of the state — from the Poconos and one-time coal towns to the central areas around Penn State University to Western Pennsylvania. He lost Philadelphia and its suburbs, but cut down the margins. In Bucks County, just north of Philadelphia, Casey was winning by less than 1 point; he carried the populous area by 6 points in 2018.

President Joe Biden narrowly won Pennsylvania in 2020 by a little more than 1 percentage point. Casey is doing worse than Biden by significant margins in almost every large county in the state, including 3 percentage points worse than Biden in Philadelphia, Montgomery, Bucks, Delaware and Chester counties. He's also underperforming Biden's 2020 performance in every region but the west, where Casey is doing about the same as Biden.

Casey led in early returns, but McCormick overtook him with about 80% of the estimated votes counted just before midnight Tuesday. Casey initially had a lead over McCormick when just about 40% of the estimated votes had been counted, propelled in part by mailed ballots that have historically favored Democrats.

McCormick was doing better in votes cast on Election Day, and as more of those ballots were counted Friday in Republican-leaning Cambria County and elsewhere, his lead grew to a margin of 0.54 percentage points by the early evening. Among the Election Day votes already counted in Cambria, McCormick is winning by a margin of 70%-27%.

That lead is likely to shrink as provisional ballots are reviewed by election officials, who will determine whether they are valid and should be added to the count. The AP's updated estimate of ballots outstanding Friday was roughly 100,000, an increase from Thursday's estimate that resulted from additional reporting on the number of provisional ballots cast statewide. In recent general elections, close to a fifth of provisional ballots in Pennsylvania are not ultimately added to the count.

CANDIDATES: Casey (D) vs. McCormick (R) and three others

WINNER: McCormick

POLL CLOSING TIME: 8 p.m. ET Tuesday

ABOUT THE RACE: Casey hails from a well-known political family in the state. The son of a popular two-term governor, he served in statewide elected office as auditor general and treasurer before being elected to the Senate in 2006. McCormick is a West Point grad, Army veteran and former investment firm CEO who lost the GOP primary to Mehmet Oz in 2022. Sharp exchanges have punctuated the contest.

McCormick accused Casey of being weak and a career politician. Casey called McCormick a wealthy, carpetbagging ex-hedge fund CEO. Pennsylvania Democrats have found success against GOP rivals in the recent Senate and governor's races.

John Fetterman beat Oz in 2022 by 5 points, and Gov. Josh Shapiro defeated Doug Mastriano handily that year as well, becoming the first governor to be elected to succeed a member of his party since 1966.

WHY AP CALLED THE RACE: McCormick was winning in regions across the state, except Philadelphia and its suburbs, though he cut Casey's margins there from six years ago. Not enough of the outstanding votes still to be counted came from areas that Casey was winning for him to close the gap.

Even if he carried six out of 10 of the outstanding votes, he still wouldn't have won. Even if there were far more ballots left to count than the AP estimates are actually remaining, and Casey were to win them by a far larger margin than he is now, he still would not win.

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