The Trump campaign also said it would file a suit to stop the counting of mail-in ballots, claiming election officials were not allowing party observers to closely monitor the process, particularly in Philadelphia. And the campaign moved to intervene in a case before the U.S. Supreme Court, hoping to stop ballots postmarked by Election Day, but received up to three days later, from being counted.
Gov. Tom Wolf, a Democrat, condemned the legal maneuvers.
“Our election officials at the state and local level should be free to do their jobs without intimidation or attacks,” Mr. Wolf said in a statement. “These attempts to subvert the democratic process are disgraceful.”
If the race comes down to the wire, the fate of thousands of provisional ballots set to be counted next week might also be in play. Many voters who requested mail-in ballots but decided to vote in person instead and did not bring their mail ballots with them to be “spoiled,” or rendered unusable, were given provisional ballots, said Bethany Hallam, a member of the elections board of Allegheny County. At least one Republican lawsuit was filed to throw out certain provisional ballots, and Ms. Hallam expects more are coming.
Mr. Trump “sent his entire legal team to Pennsylvania to try to invalidate legal votes in whatever way possible,” Ms. Hallam said.
No matter who ends up winning the battle for Pennsylvania, the geography and the closeness of the race revealed a state pulling ever further apart along regional and partisan lines. Suburbs outside Philadelphia and Pittsburgh that once leaned Republican have become treacherous for the party under Mr. Trump, while blue-collar counties, where Democrats used to win election after election, have moved to the populist right.
Mr. Biden, a Scranton native whose pitch to Democrats was always that he could woo back white working-class voters, fell short of that goal. Although he slightly narrowed margins in rural counties compared with Hillary Clinton in 2016, Mr. Trump, who barnstormed through the state’s most conservative regions, brought out even more of his base.
In Washington County in southwest Pennsylvania, a region that benefited economically from fracking for natural gas, Mr. Biden won a slightly larger share of the vote than Mrs. Clinton did, 38 percent versus 35 percent. But with overall turnout up significantly, Mr. Trump won 9,300 more raw votes this year than he did in 2016, while Mr. Biden added only 7,650 additional votes. The pattern appears to have repeated across central Pennsylvania.