PHILADELPHIA (NewsNation Now) — Democrat Joe Biden is leading President Donald Trump by a narrow margin in the battleground state of Pennsylvania.

By Friday morning, Biden overtook Trump in the number of ballots counted in the state, which Trump must win to have a shot at reelection. Biden leads by more than 9,000 votes. The contest is still too early for The Associated Press to call. Votes in the state are still being counted.

City officials in Philadelphia held an election operations update Thursday afternoon where they said more results were expected to be released later in the day.

“We’re going to continue to count the ballots as quickly as we can without sacrificing accuracy as we have since the beginning,” said City Commissioner Lisa Deeley. “We are ensuring that the ballots that we have are counted as quickly and accurately as possible.”

Philadelphia Mayor Jim Kenney said he believed Biden was going to be elected.

“I think what the president needs to do is frankly put his big boy pants on,” said Kenney. “Stop this and let us move forward as a country.”

Trump’s lead dwindled after Election Day when state officials began processing mail-in ballots, a form of voting that has skewed heavily in Biden’s favor. Trump spent months claiming — without proof — that voting by mail would lead to widespread voter fraud.

If there is less than a half percentage point difference between Biden’s and Trump’s vote totals, state law dictates that a recount must be held.

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.

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.

NewsNation’s television broadcast and digital properties relies on the AP for all vote counting and race calls. NewsNation chose to rely on the AP because they call races based on the facts.