US President Donald Trump and his White House challenger Joe Biden clashed over Covid and race while trading corruption charges, in their final live TV debate.

On the pandemic, Mr Biden would not rule out more lockdowns, while Mr Trump insisted it was time to reopen the US.

Mr Trump cited unsubstantiated claims Mr Biden personally profited from his son's business dealings. The Democrat brought up Mr Trump's opaque taxes.

Trump, 74, will hold two rallies in the battleground state of Florida, where opinion polls show a tight race. Biden, 77, will deliver a speech in his home state of Delaware on his plans for leading a recovery from the pandemic.

More than 47 million Americans already have cast ballots in person or through the mail - roughly eight times the number of early votes cast at about the same point in 2016 - giving Trump, who is trailing in national opinion polls, fewer opportunities to change minds before voting ends on Nov. 3.

The pandemic has upended campaign traditions and its effects still are being felt. Americans may find themselves waiting days or weeks to know who won as election officials count tens of millions of mail-in votes.

Biden enters the final days of the race with more cash than Trump. The Democrat raised about $130 million during the Oct. 1-14 period, about three times the roughly $44 million raised by the Republican Trump’s campaign, according to disclosures filed on Thursday with the Federal Election Commission.