The so-called blue wall states — Michigan, Wisconsin and Pennsylvania — were long expected to play a pivotal role in the 2020 election, and that is indeed coming to pass.
By midday on Wednesday, Joseph R. Biden Jr. was declared the winner in Wisconsin and a few hours later he won Michigan. In Pennsylvania, President Trump had an edge, but large numbers of early votes and results from Democratic strongholds like Philadelphia were still being processed.
Mr. Biden won Wisconsin with a 20,000-vote lead over Mr. Trump. And he led with 67,000 votes ahead of the president to take Michigan.
Here is a look at where things stand as the counting continues in Pennsylvania and how the races in Michigan and Wisconsin led to Biden victories.
Perhaps no state is staring down a longer counting period than Pennsylvania. As of midday Wednesday, 5.7 million votes had been counted in Pennsylvania, which represented roughly 80 percent of the estimated vote total in the state.
They got a late start. The state legislature refused to allow election officials to begin processing absentee ballots until 7 a.m. on Election Day, and officials across the state were laboring through the tedious process of counting ballots.
In Philadelphia, only 76,000 absentee ballots out of more than 350,000 were processed in the first 14 hours that officials were allowed to count ballots. Though Philadelphia election officials were working around the clock on the absentee ballots, the pace indicated that the count could last into Thursday.
Other major counties, like Chester, Montgomery and Delaware, suburban counties outside of Philadelphia and a growing source of strength for Democrats, also had not reported the majority of their mail-in ballots. Allegheny County, home to Pittsburgh and another Democratic base of support, still had a large share of ballots to count.
Senator Bob Casey Jr., a Democrat, said, “I’m confident Joe Biden will carry the state because of the margins we’ll get in those counties.”
Though Mr. Trump had a roughly 400,000-vote advantage in Pennsylvania, Democrats in the state were confident that they could make up the margins with votes from Philadelphia and the “collar counties” surrounding it still to be counted.
The delays in results in Pennsylvania, however, might extend beyond the simple challenge of counting the outstanding ballots. Republicans filed multiple lawsuits in the state on Tuesday, including one regarding provisional ballots for voters who had their absentee ballots rejected.
Early Wednesday, national Democrats filed a motion intervening in Montgomery County. Hearings were scheduled in both state and federal court on Republican lawsuits, and lawyers on both sides were anticipating further litigation in Pennsylvania.
Early returns were inconclusive on Tuesday evening, but Mr. Biden was declared the winner Wednesday afternoon, after key population centers such as Milwaukee reported its vote tally. The numbers trickled in early Wednesday morning, when a large vote count from that city was announced, and Mr. Biden edged ahead of Mr. Trump based on roughly 97 percent of estimated votes statewide. The final vote tally put the Democratic nominee ahead by about 20,000 votes — a similar margin to what Mr. Trump won the state by four years ago.
The state gives Mr. Biden one of his first victories in a state Mr. Trump won in 2016. The victory was powered by increased turnout in Madison, reaching a little over 75 percent, according to election officials. In Milwaukee, another of the state’s liberal strongholds, turnout seemed better than four years ago but not at the same high levels as in other major cities in battleground states from Arizona to North Carolina.
The state’s final total was much closer than many Democrats expected. Mr. Biden built a political campaign focused on Midwestern voters, aimed at clawing back many of the ideological moderates who voted for Mr. Trump in 2016. Still, Mr. Trump showed continued strength in rural and suburban areas, making the final vote margin much closer than many polls expected.
Because of the small percentage between both candidates, Mr. Trump’s campaign announced it would seek a recount under state law. Democrats and Republicans officials, however, expected the state to stay within Mr. Biden’s column even after the legal challenge.
Mr. Biden took a slim lead in the state early Wednesday, as some of the state’s major population centers began reporting the large numbers of ballots that were cast early and unaccounted for late Tuesday. By early Wednesday evening, he was declared the winner in the state, remaining more than 67,000 votes ahead of Mr. Trump.
Polls taken before the election had shown the former vice president considerably ahead, outside the margin of error. He won by 1.2 percentage points.
An earlier edge for Mr. Trump reflected his advantage in the Election Day vote — not the early vote, which was a larger share of the overall ballots cast in the state and favored Mr. Biden.
In Detroit, the city clerk had counted only about half of what was expected. The clerk’s office had reported having about 240,000 votes tallied by midday Wednesday. Later on Wednesday, more than 833,000 votes were reported.
For comparison purposes, Detroiters cast 248,000 ballots in 2016, when turnout was low. This year, election officials have said they expect turnout to easily surpass that, potentially exceeding 2008 and 2012, when President Barack Obama was on the ballot.
Mr. Biden won more than 67 percent of the vote in Detroit.
In Michigan’s bellwether Macomb County, which voted twice for Mr. Obama and then for Mr. Trump in 2016, the president was ahead with most of the ballots counted, but not by as much as he was four years ago when he carried it by more than 11 percentage points. Once Macomb counted its early and Election Day ballots, Mr. Biden was able to close a considerable gap, as he had in many counties throughout the day as the same-day ballots were counted first.
And in Oakland County, the state’s second-largest, what began as a significant lead for Mr. Trump on Tuesday evening vanished into an advantage for Mr. Biden by Wednesday as more and more precincts reported their early votes.
Democrats have won Oakland County in every recent presidential election. Hillary Clinton carried it by eight points in 2016, and Mr. Biden carried the county by 14 points.