Ballot counting continues in five states that are set to decide the outcome of Tuesday’s vote, unless a Trump campaign legal challenge winds its way to the Supreme Court and the judges have the final say.
Some projections have Mr Biden just one state away from reaching the 270 Electoral College votes (out of 538) that are required to become president, but Mr Trump still has a path to that magic number.
As of Thursday afternoon, Mr Biden had 264 and Mr Trump had 214 by some tallies, and the Democrat could be able to declare himself the winner when a clearer picture emerges soon in Nevada, which has six electoral votes.
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If Mr Biden wins Nevada and reaches the threshold of 270, Mr Trump will continue to contest the outcome and press ahead with his legal battle.
Like the vote in 2000, this election result could end up being decided by Supreme Court, where the conservatives have a 6-3 super majority.
Two days on from Tuesday’s election, the race has come down to five key battleground states that are still too close to call – Arizona, Georgia, Nevada, North Carolina and Pennsylvania. Millions of mail-in and absentee votes are still being counted.
Mr Biden is leading in Arizona and Nevada, while Mr Trump is ahead in Georgia, North Carolina and Pennsylvania.
How can Donald Trump win?
Real estate mogul Mr Trump, 74, has already falsely declared victory and baselessly alleged voting fraud.
He is launching a multi-state legal battle to hold onto the White House in the event that he loses the Electoral College vote.
His campaign is suing to stop ballot counting in Georgia, Michigan and Pennsylvania, with Democrats fearing Mr Trump could ‘steal’ victory away from Mr Biden with a successful legal challenge.
The president is seeking a recount in Wisconsin and is expected to take legal action in Nevada.
Mr Trump still has a path to 270, although his odds are much slimmer than those of Mr Biden’s.
The Republican president can retain the White House by holding his leads in Georgia, North Carolina and Pennsylvania, and winning at least one state where Mr Biden is currently leading.
Mr Trump’s leads in the must-win states of Georgia, North Carolina and Pennsylvania aren’t safe at this stage.
They were narrowing as mail-in and absentee votes were being counted.
Mr Trump is at risk of becoming the first incumbent US president to lose a re-election bid since fellow Republican George HW Bush in 1992, who was defeated by Bill Clinton.
How can Joe Biden win?
At this stage, Mr Biden, 77, seems to have the easiest path to victory, as he needs only just one more state to win,according to some projections, and he holds a slight lead in Nevada.
He will reach the required 270 electoral votes if he holds his leads in Nevada, where an updated ballot count will be released from 9am local time (5pm UK time) on Thursday, and Arizona, which he has been tipped to win.
Some US networks, including CNN and NBC News, have not yet declared a winner in Arizona because the margin is razor thin and there are many ballots still to be counted.
The Democrat still has a chance to win Georgia or Pennsylvania, where Mr Trump holds narrow leads as ballots from heavily-populated cities and counties that traditionally lean blue are still being counted.
If Mr Biden wins Georgia or Pennsylvania, he can afford to lose Arizona and Nevada.
North Carolina is also considered a toss-up.
The former vice president to Barack Obama predicted victory on Wednesday and launched a website to begin the transition to a Democratic-controlled White House.
Mr Trump is launching legal battles in multiple states, meaning it could be several weeks before a winner is officially declared.
The situation has echoes of 2000, when the Supreme Court intervened and stopped a recount in Florida, handing victory to Republican candidate George W Bush over his Democratic rival Al Gore.
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Before the election, Mr Trump predicted a court fight and even signalled he wouldn’t concede, agree a peaceful transfer of power or willingly leave the White House.
December 8 is the deadline to resolve election disputes. The president is sworn into office on January 20, 2021.
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