Democratic presidential candidate and US Vice President Kamala Harris will urge Americans to turn the page on Donald Trump as she delivers her closing election argument on Tuesday on the spot where her Republican rival rallied supporters before the January 6, 2021 US Capitol attack.

With polls in a dead heat one week before Election Day, Harris’ campaign said she chose the symbolic site to push her case that the Republican former president is a threat to American democracy.

It said in a statement that the former prosecutor would deliver a "major closing argument" and "make the case that it is time to turn the page on Trump and chart a new way forward.”

A senior campaign official said Harris will also deliver an "optimistic and hopeful" message, amid rumblings in the party that she is focusing too much on Trump and not enough on her own policies.

Harris will address some 20,000 people on the Ellipse, a park outside the White House where Trump delivered a fiery speech in which he ramped up his false claims that he won the 2020 election.

Trump supporters then marched on the Capitol to disrupt the certification of Joe Biden's victory, in an assault that left at least five people dead and 140 police officers injured.

For his part, Trump, who, at 78, is the oldest presidential candidate in US history, will be trying to take the sting out of Harris' big event by delivering remarks at his Mar-a-Lago resort in Florida.

He will then rally in blue-collar Allentown in Pennsylvania, perhaps the most crucial of the seven battleground states that are expected to decide the election.

Trump gave his closing arguments at a mass rally at New York's Madison Square Garden at the weekend, where some of the other speakers used language widely condemned as racist and sexist.

Both candidates will keep up a punishing schedule in the final days until November 5, sometimes hitting three or more states in one day. (AFP)