WASHINGTON (AP) — A handful of pivotal states remained in play Thursday in the tightly contested U.S. presidential race. Here, The Associated Press reviews them and examines the reasons why they could still go to either Republican Donald Trump or Democrat Joe Biden:

___

GEORGIA: Outstanding ballots left to be counted in counties where Biden has performed well.

THE BACKGROUND: Early Wednesday, Trump prematurely claimed he carried Georgia.

"It's ... clear that we have won Georgia. We're up by 2.5%, or 117,000 (votes) with only 7% (of the vote) left" to count, Trump said during an early morning appearance at the White House. He also said he planned to contest the U.S. presidential election before the Supreme Court. It was unclear exactly what legal action he might pursue.

The race is too early to call. With an estimated 99% of the vote counted there, Trump's lead over Biden has shrunk to about 13,000 votes, with tens of thousands more ballots left to be counted.

That includes mailed ballots from population-dense counties in the Atlanta metro region that lean Democratic. Biden is overperforming Hillary Clinton's 2016 showing in those counties, including in their more upscale suburban reaches.

___

NEVADA: Race too early to call; vote count will continue for several more days.

THE BACKGROUND: Democrat Joe Biden leads by less than 1 percentage point in Nevada over President Donald Trump, with more than 1.2 million ballots counted.

That's after election officials in Nevada released updated returns on Thursday, including a batch of 14,285 and 12,189 ballots, respectively, in the state's two largest counties, Clark and Washoe.

Overall, officials have tallied a little more than three-quarters of the state's expected vote. Under state law, ballots postmarked by Election Day will still be counted if they arrive by Tuesday, Nov. 10. Clark County said Thursday it did not expect to complete counting the bulk of its mail votes until this weekend.

Among the ballots still left to be processed in Nevada this year are provisional ballots, including 60,000 in Clark County, where most of the state's voters live. Those ballots were mostly cast by voters who registered on Election Day and will be counted after officials verify their eligibility to be included.

Trump narrowly lost Nevada in 2016. The state has trended toward Democrats in the past decade. The last Republican presidential contender to win the state was George W. Bush in 2004. In that year, AP did not call the winner of the election in Ohio until it was able to confirm that Bush's lead exceeded the number of provisional ballots left to be counted.

Biden's lead in Nevada stands at 11,438 votes.

___

NORTH CAROLINA: Race too early to call. Ballots left to count.

THE BACKGROUND: Trump prematurely claimed early Wednesday that he won the state.

"We've clearly won North Carolina, where we're up 1.7%, 77,000 votes with only approximately 5% left. They can't catch us," he said during an appearance at the White House. Trump also said he planned to contest the U.S. presidential election before the Supreme Court. It was unclear, exactly, what legal action he might pursue.

Though Trump is correct that he held a nearly 77,000-vote lead, which he maintained Thursday morning, the race is too early to call with up to 116,000 mail ballots left to count, as well as about 41,000 provisional ballots statewide.

As long as those ballots are postmarked by Nov. 3, state election officials have until Nov. 12 to count them. And when it comes to mail ballots, Biden was outperforming Trump. That means the ballots yet to be counted could give Biden a lead.

___

PENNSYLVANIA: Hundreds of thousands of votes left to be counted.

THE BACKGROUND: Pennsylvania is among a handful of battleground states Trump and Biden are narrowly contesting, and there were hundreds of thousands of votes left to be counted Thursday morning.

Trump, who held a 675,000-vote lead early Wednesday, prematurely declared victory in the state.

"We're winning Pennsylvania by a tremendous amount. We're up 690,000 votes in Pennsylvania. These aren't even close. It's not like, 'Oh, it's close,'" Trump said during an appearance at the White House.

By Thursday afternoon, his lead had slipped to about 114,000 — and the race is destined to get tighter.

One reason is because elections officials are not allowed to process mail-in ballots until Election Day under state law. It's a form of voting that has skewed heavily in Biden's favor after Trump spent months claiming without proof that voting by mail would lead to widespread voter fraud.

Mail ballots from across the state that were counted by late Wednesday overwhelming broke Biden's direction.

A final vote total may not be clear for days because the use of mail-in ballots, which take more time to process, has surged as a result of the coronavirus pandemic.

Democrats had long considered Pennsylvania a part of their "blue wall" — a trifecta that also includes Wisconsin and Michigan — that for years had served as a bulwark in presidential elections. In 2016, Trump won each by less than a percentage point.

Biden, who was born in Scranton, claims favorite-son status in the state and has long played up the idea that he was Pennsylvania's "third senator" during his decades representing neighboring Delaware. He's also campaigned extensively in the state from his home in Delaware.