A close margin and a large number of outstanding votes are what's making the Pennsylvania contest between President Donald Trump and Joe Biden too early to call.
The Democrat opened a lead of more than 9,853 votes Friday morning over Trump, of more than 6.5 million votes cast -- a lead of about 0.15%. State law dictates that a recount must be held if the margin between the two candidates is less than 0.5%. There are tens of thousands of votes left to count.
Additionally, about 85,000 provisional ballots from 56 counties were outstanding. Those ballots will be counted after officials verify their eligibility to be included.
Pennsylvania is among a handful of battleground states Trump and Biden are narrowly contesting as they seek the 270 electoral votes needed to win the presidency.
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.
The late-counted ballots were overwhelmingly in Biden's favor.
One reason the race tightened: Under state law, elections officials are not allowed to process mail-in ballots until Election Day. 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.
There's a possibility the race won't be decided for days. If there is less than a half percentage point difference between Biden and Trump's vote total, state law dictates that a recount must be held.
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.