The fate of the United States presidency hung in the balance Wednesday, as President Donald Trump and Democratic challenger Joe Biden battled in familiar battleground states — and some unexpected ones — that will prove crucial in determining who wins the White House.

It was unclear when or how quickly a winner could be determined. A burst of votes in Michigan and Wisconsin gave Biden a small lead in those states, but it was still too early to call the race. Hundreds of thousands of votes were also outstanding in Pennsylvania.

The high-stakes election was held against the backdrop of a historic pandemic that has killed more than 230,000 Americans and wiped away millions of jobs. Both candidates spent months providing dramatically different visions for the nation’s future and voters responded in huge numbers, with more than 100 million casting votes ahead of Election Day.

Here are five states we’re watching as the second day of counting votes continues:

  1. Georgia
  2. Michigan. UPDATE: President Trump is filing a lawsuits in Michigan to stop the counting of ballots until the campaign is given “meaningful access to numerous counting locations to observe opening of ballots.”
  3. Wisconsin. UPDATE: Biden has won Wisconsin, and the president’s reelection campaign is officially requesting a recount.
  4. Pennsylvania
  5. North Carolina

The Associated Press has not declared a winner in the presidential race. There are still hundreds of thousands of votes left to be counted, and the outcome hinges on a handful of uncalled battleground states.

"We’re still in the game in Georgia, but that’s not one we expected,” Biden said early Wednesday. “It’s going to take some time to count the votes, but we’re going to win Pennsylvania. We can know the results as early as [Wednesday] morning, but it could take a little longer.”

»Click here for live U.S. results.

Trump made a statement nearly two hours later from the East Room of the White House. He said it was “clear we have won Georgia,” although the state hadn’t been called yet while ballots were still being counted.

“I want to thank the American people for their tremendous support,” Trump said.

But the margins were exceedingly tight, with the candidates trading wins in battleground states across the country. Trump picked up Florida, the largest of the swing states, while Biden flipped Arizona, a state that has reliably voted Republican in recent elections. Neither cleared the 270 Electoral College votes needed to carry the White House.

Trump defeats Biden in Florida

Biden, briefly appearing in front of supporters in Delaware, urged patience, saying the election “ain’t over until every vote is counted, every ballot is counted.”

“It’s not my place or Donald Trump’s place to declare who’s won this election,” Biden said. “That’s the decision of the American people.”

Vote tabulations routinely continue beyond Election Day, and states largely set the rules for when the count has to end. In presidential elections, a key point is the date in December when presidential electors meet. That’s set by federal law.

Several states allow mailed-in votes to be accepted after Election Day, as long as they were postmarked by Tuesday. That includes Pennsylvania, where ballots postmarked by Nov. 3 can be accepted if they arrive up to three days after the election.

Pennsylvania Gov. Tom Wolf tweeted that his state had more than 1 million ballots to be counted and that he “promised Pennsylvanians that we would count every vote and that’s what we’re going to do.”

Trump appeared to suggest those ballots should not be counted, and that he would fight for that outcome at the high court. But legal experts were dubious of Trump’s declaration.

“I do not see a way that he could go directly to the Supreme Court to stop the counting of votes. There could be fights in specific states, and some of those could end up at the Supreme Court. But this is not the way things work,” said Rick Hasen, a professor of law and political science at the University of California-Irvine.

Trump has appointed three of the high court’s nine justices including, most recently, Amy Coney Barrett.

Democrats typically outperform Republicans in mail voting, so the GOP looked to make up ground in Election Day turnout. That meant the early margins between the candidates could be influenced by which type of votes — early or Election Day — were being reported by the states.

Trump kept several states, including Texas, Iowa and Ohio, where Biden had made a strong play in the final stages of the campaign. But Biden also picked off states where Trump sought to compete, including New Hampshire and Minnesota. But Florida was the biggest, fiercely contested battleground on the map, with both campaigns battling over the 29 Electoral College votes that went to Trump.

The president adopted Florida as his new home state, wooed its Latino community, particularly Cuban-Americans, and held rallies there incessantly. For his part, Biden deployed his top surrogate — President Barack Obama — there twice in the campaign’s closing days and benefited from a $100 million pledge in the state from Michael Bloomberg.

Democrats entered the night confident not only in Biden’s prospects but also in the the party’s ability to take control of the Senate. But the GOP held several seats that were considered vulnerable, including in Iowa, Texas and Kansas. The House was expected to remain under Democratic control.

The momentum from early voting carried into Election Day, as an energized electorate produced long lines at polling sites throughout the country. Turnout was higher than in 2016 in numerous counties, including all of Florida, nearly every county in North Carolina and more than 100 counties in both Georgia and Texas. That tally seemed sure to increase as more counties reported their turnout figures.