With his re-election chances fading as more votes are counted in a handful of battleground states, U.S. President Donald Trump launched an extraordinary assault on the country's democratic process from the White House on Thursday, falsely claiming the election was being "stolen" from him.

Offering no evidence, Trump lambasted election workers and alleged fraud in the states where results from a dwindling set of uncounted votes are pushing Democrat Joe Biden nearer to victory.

US elections 2020
US elections 2020. Reuters

"This is a case where they're trying to steal an election," Trump said, who spoke for about 15 minutes in the White House briefing room before leaving without taking questions.

Biden, the former vice president, was steadily eating away the Republican incumbent's leads in Pennsylvania and Georgia even as he maintained narrow advantages in Nevada and Arizona, moving closer to securing the 270 votes in the state-by-state Electoral College that determines the winner.

In Pennsylvania, Trump's lead had shrunk from 319,000 on Wednesday afternoon to 64,000 a day later, while his margin in Georgia fell from 68,000 to fewer than 4,000. Those numbers were expected to continue to move in Biden's favor, with many of the outstanding ballots from areas that typically vote Democratic, including the cities of Philadelphia and Atlanta.

Biden, meanwhile, saw his lead in Arizona contract from 93,000 to 65,000; he was ahead in Nevada by only 11,000 votes.

Biden would become the next president by winning Pennsylvania, or by winning two out of the trio of Georgia, Nevada and Arizona. Trump's likeliest path appeared narrower - he needed to hang onto Pennsylvania and Georgia while overtaking Biden in either Nevada or Arizona.

Most major television networks gave Biden a 253 to 214 lead in Electoral College votes, which are largely determined by state population, after he captured the crucial states of Wisconsin and Michigan on Wednesday.

As demonstrators marched in several U.S. cities for a second straight day, the election lay in the hands of civil employees who were methodically counting hundreds of thousands of ballots, many of which were sent by mail amid the coronavirus pandemic.

Final results in each state could take days. Pennsylvania Secretary of State Kathy Boockvar said on Thursday afternoon the state still had about 350,000 ballots yet to count but expected the vast majority to be tallied by Friday.

In Georgia, Gabriel Sterling, an election official, said it would "take time" to process tens of thousands of remaining ballots. Arizona, where there were at least 400,000 ballots remaining, and Nevada, which had 190,000 uncounted votes, were also expected to take days to complete their tallies.

'MESSY' DEMOCRACY

Trump's remarks followed a series of Twitter posts from Trump earlier in the day that called for vote counting to stop, even though he currently trails Biden in enough states to hand the Democrat the presidency.

Trump's campaign, meanwhile, pursued a flurry of lawsuits in Georgia, Michigan, Nevada and Pennsylvania, though judges in Georgia and Michigan quickly rejected the challenges. Legal experts said the cases had little chance of affecting the electoral outcome.

Biden wrote on Twitter shortly after Trump's White House appearance, "No one is going to take our democracy away from us." In earlier remarks from his hometown of Wilmington, Delaware, Biden expressed confidence he would win and urged calm as votes were tallied.

"Democracy's sometimes messy," Biden said. "It sometimes requires a little patience as well. But that patience has been rewarded now for more than 240 years in a system of governance that has been the envy of the world."

A new Reuters/Ipsos poll showed a bipartisan majority of Americans rejecting Trump's premature victory declaration in favor of counting all votes. The close election underscored the nation's deep political divides, while the slow count of millions of mail-in ballots served as a reminder of the deadly pandemic that continues to upend American life.

Trump Biden

Biden, if he prevails, will nevertheless have failed to deliver the sweeping repudiation to Trump that Democrats had hoped for, reflecting the deep support the president enjoys despite his tumultuous four years in office. Trump's influence on the Republican Party will remain strong, even if he ultimately loses a tight election.

The winner will face a pandemic that has killed more than 234,000 Americans and left millions more out of work, even as the country still grapples with the aftermath of months of unrest over race relations and police brutality.

Biden led Trump by more than 3.9 million in the national popular vote, though that plays no role in deciding the winner. Trump lost the popular vote by about 3 million to Democrat Hillary Clinton in 2016, when he secured an upset victory by winning key states in the Electoral College. He is trying to avoid becoming the first incumbent U.S. president to lose a re-election bid since fellow Republican George H.W. Bush in 1992.

Trump, who often relished legal battles during his turbulent business career, was at the White House working the phones and monitoring developments on television, two Trump advisers said. He has been talking to state governors as well as close friends and aides and dispatched some of his closest advisers out in the field to fight for him.

"He's very engaged, he's monitoring, talking to all the states," a Trump confidant said. "It doesn't look good but this guy wants to keep fighting. He's in a fighting mood right now. He's not melancholy or dejected. But the path is getting harder and harder." Twitter and Facebook have flagged numerous posts from Trump since Election Day as misleading.

Trump's rhetoric had gained traction with some supporters, however. A Facebook group called "Stop the Steal" pushing false claims of voter fraud gained hundreds of thousands of members on Thursday before the social media giant took down the page, citing calls for violence. Supporters of both candidates also held small protests outside voting centers on Thursday, though the demonstrations were largely peaceful.