PHILADELPHIA, United States (AFP) — Kamala Harris and Donald Trump are poised to face off in a high-stakes televised debate Tuesday, a potentially game-changing moment less than two months ahead of the United States (US) presidential election.

The stakes could hardly be higher for the Democratic vice president and Republican former president with tens of millions of American voters expected to tune in at 9:00 pm Eastern Time (0100 GMT Wednesday) to watch them take the stage for their first and possibly only debate.

A single zinger or gaffe could tip the balance of one of the most dramatic White House races in US history, with the two rivals neck-and-neck in the polls ahead of the November 5 vote.

For Harris, 59, it will be a critical chance to win over voters who still know little about her, as her honeymoon starts to fade after suddenly replacing President Joe Biden in July.

Trump, 78, will meanwhile try to box in Harris on issues like the economy and immigration, but may also unleash more of the racist and sexist insults that he’s directed her way during the campaign.

Harris, who enjoys a significant advantage among women according to the polls, is expected to press Trump on reproductive rights after he made a number of seemingly contradictory comments recently on abortion access.

The two candidates will be meeting in person for the first time at the ABC News debate in Philadelphia, adding to the potential for a bruising confrontation.

“This debate may go down in the history books. Break out the popcorn,” said Andrew Koneschusky, a former press secretary for Senate leader Chuck Schumer.

The ABC News debate is scheduled to last for 90 minutes and will be held without an audience.