The nationally watched U.S. Senate race in Pennsylvania between Democratic incumbent Bob Casey Jr. and Republican challenger Dave McCormick was still too close to make a decision as of mid-morning Wednesday.

While Casey held the lead for most of the campaign, the race has become tighter in recent days.

“In areas like Philadelphia, more votes need to be counted, and it is important that every legal ballot is counted,” Casey spokeswoman Maddy McDaniel said Wednesday morning. “If that happens, we are confident the senator will be re-elected.”

Shortly after 11:30 p.m. Tuesday, Sam DeMarco, chairman of the Allegheny Republican Committee, told McCormick supporters gathered in Pittsburgh that he was “very encouraged” by the early results.

“We’re going to make history tonight,” he said.

With more than 95% of the votes counted, Casey was trailing by almost 50,000 votes by late morning. But ballots still needed to be counted in southeastern Pennsylvania, including up to 35,000 in Philadelphia.

A McCormick victory would oust a three-term incumbent with exceptional name recognition. Casey's father was governor of Pennsylvania, and Casey, a mild-mannered centrist, has held public office in Pennsylvania since 1996. McCormick, a West Point graduate and Gulf War veteran, is a former hedge fund executive who profited from tens of millions in spending by a super PAC funded by billionaires in the financial industry.

With Republicans picking up seats in West Virginia and Ohio, the race won't determine control of the Senate but could play an important role in determining the strength of the Republicans' expected majority. If Casey and a handful of other Democratic incumbents survive, Republicans will have little room to defect from the upper chamber over the next two years.

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Both campaigns expected a close race, although Casey started with a significant lead in the polls due to Pennsylvania voters' greater familiarity. Thanks in part to a months-long barrage of TV advertising, McCormick's profile grew, and the contest was widely viewed in recent weeks as a false decision.

More than $300 million was spent on the race by the campaigns, their parties and outside fundraising groups. The largest outside donor was Keystone Renewal, a pro-McCormick super PAC backed primarily by financial industry billionaires, some of whom knew the Republican from his days at Bridgewater in Connecticut.

McCormick, who narrowly lost the 2022 Republican Senate primary to Mehmet Oz, this time found a message that resonated with voters worried about the economy — and eager to support a candidate aligned with former President Donald Trump is an ally.

McCormick “has a great background in business,” said Mary Dodgi, 80, a retired teacher who lives in Ross Township in Pittsburgh's North Hills and was a registered Democrat until a decade ago. Now, she said, McCormick and Trump represent the party “for the people.”

Casey loyalists favored the moderate message of the Scranton native, who served as the state's comptroller general and treasurer before making national headlines in 2006 by unseating conservative U.S. Sen. Rick Santorum.

Michael Marko, 66, who was volunteering outside polls at the Cione Rec Center in Port Richmond on Tuesday, said he believes Casey is the “most important candidate on the ballot.”

“Casey will keep Trump in check,” Marko said.

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Casey's politics have shifted left over the years on issues such as abortion and same-sex marriage. But he has stuck to a populist economic agenda by supporting organized labor, opposing efforts to restrict the natural gas industry and fighting free trade deals, including those proposed by Democratic presidents.

This year, Casey's message on inflation – he calls it “greed inflation” and blames it on profit-hungry corporations rather than government spending – was embraced by the campaign of Vice President Kamala Harris and other Democrats.

Casey is a simple Democratic senator who preaches the virtues of bipartisan civility, while McCormick is a clean-cut army man turned businessman. And while neither man was afraid to attack the other on the campaign trail, there was little drama in the race, and voters faced a relatively simple choice between a career politician and a plutocratic newcomer.

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Throughout the race, McCormick faced questions about his ties to the Commonwealth. This year it was reported that he had repeatedly flown on private jets back to Connecticut, where one of his daughters from a previous marriage still lives.

Those questions turned off some lifelong Republican voters, including Joyce Sanyour, 70, who said her decisions this election cycle were guided by her views on abortion access and her concerns about political incivility. “And I’m not sure where Dave McCormick lives,” she said.

But on Tuesday night, Casey's supporters at his election watch party in Scranton appeared disheartened.

“As the night went on, we got sadder and sadder,” said Eunice Gray, 52, before getting into her car and making the 40-minute drive home to Stroudsburg. “It feels like 2016 again, as opposed to 2020.”

Her husband, Curtis Gray, said he worries about the future of the country if Trump and McCormick prevail.

“This country is divided enough,” he said.

— Staff writers Aubrey Whelan and Beatrice Foreman contributed to this story.