Democratic presidential nominee Joe Biden (R) and vice presidential nominee Sen. Kamala Harris (L) leave the stage after addressing the nation at the Chase Center Nov. 6, 2020 in Wilmington, Delaware. (Getty/Kyodo)

Democratic presidential candidate Joe Biden was on the cusp of capturing the White House on Saturday as his lead grew over President Donald Trump in Pennsylvania, one of four key battleground states that will determine the final outcome.

Biden edged closer to victory on Friday, three days after Election Day, when he overtook Trump in Pennsylvania, whose 20 electoral votes would put the former vice president over the 270 threshold needed to win the presidency.

"We're going to win this race," Biden said in his home state of Delaware late Friday, though he stopped short of declaring victory because vote counting was continuing.

As of Saturday morning, Biden led the GOP president by 28,833 votes in Pennsylvania with 96 percent of the vote counted, according to The New York Times.

Biden's slim lead in Georgia widened to 7,248 votes with the count 98 percent complete, while his lead narrowed to 29,861 votes in Arizona with 97 percent of the tally completed, the paper said.

In Nevada, Biden led by 22,657 votes with 93 percent of the count complete.

Biden said Friday that Americans had given him and his vice presidential running mate, Sen. Kamala Harris, a mandate to address the coronavirus pandemic, the virus-hit economy, climate change and systemic racism.

"They made it clear. They want the country to come together, not continue to pull apart," he said.

Seeing his earlier edge diminish in Pennsylvania and Georgia, Trump insisted the election was "rigged" through "illegal" ballots, alluding to mail-in ballots he has baselessly criticized as vulnerable to voter fraud.

President Donald Trump makes a statement in the Brady Press Briefing Room at the White House in Washington on Nov. 5, 2020. (UPI/Kyodo)

"We have said that all legal ballots must be counted and all illegal ballots should not be counted, yet we have met resistance to this basic principle by Democrats at every turn," he said in a statement.

Election officials, however, say there has been no evidence of widespread fraud.

Trump showed no sign he was ready to concede, as his campaign engaged in a series of lawsuits that legal experts said are unlikely to change the election results.

The number of ballots cast by mail -- which surged to the tens of millions amid worries about in-person voting during the pandemic -- has led to a protracted vote counting process, leaving the outcome still up in the air.


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