Trump also insisted he won the debate, and has so far rejected calls by Harris’ campaign for another face-off before voters head to the polls.

“Vice President Harris is ready for a second debate. Is Donald Trump?” said campaign chair Jen O’Malley Dillon.

On social media, Trump replied: “In the world of boxing or UFC, when a Fighter gets beaten or knocked out, they get up and scream ‘I DEMAND A REMATCH, I DEMAND A REMATCH!’ Well it’s no different with a Debate. She was beaten badly last night… so why would I do a rematch?”

Tuesday’s debate between Harris and the former president was the first time the pair met, and a pivotal chance to woo undecided voters as the race tightens.

Both candidates presented contrasting visions: Trump portrayed America as a “country in decline” that would get worse if a “radical Liberal” was elected president, while Harris cast herself as a “new way forward” and her opponent as a relic of the past.

But even some of Trump’s conservative allies expressed frustration that he veered off course repeatedly and struggled to stay disciplined.

“The Harris campaign has said for a week that it was going to try to get under Trump’s skin by poking fun at his rallies. It worked,” said conservative radio host Erick Erickson.

In reference to the online conspiracy theories about Haitian immigrants, Erickson added: “Trump was also having to deal with the morons of the right, who got in his head and filled him up with a bunch of nonsense before he got on stage.

Democrats, on the other hand, praised Harris’s performance, which followed days of preparation at a Pittsburgh hotel. It included multiple practice runs, a mock setup mimicking the debate studio layout, and an aide playing Trump to simulate attacks.

Hillary Clinton – who debated Trump ahead of the election in 2016 – also provided advice to Harris, telling her the Republican could be easily triggered.

After the debate, Taylor Swift gave Harris her biggest endorsement yet and urged her fans to do their own research and register to vote. Swift had previously endorsed Biden in 2020 and, in 2018, backed Tennessee’s Democratic Senate candidate, Phil Bredesen, who was running against Republican Marsha Blackburn, whom Swift described as “Trump in a wig.”

Trump called into Fox & Friends on Wednesday morning, saying he was not a fan of Taylor Swift and that her endorsement was “just a matter of time.”

He also criticised co-moderators David Muir and Linsey Davis, who fact-checked him five times during the debate, correcting false claims on issues including abortion (where he claimed some Democrats were “OK” with babies being “executed” after birth) and immigration (he was rebuked for a conspiracy theory about Haitian immigrants).

The moderators did not apply the same scrutiny to Harris, who also made exaggerated claims about Trump’s ties to the Project 2025 presidential transition plan and the amount of money the Biden-Harris administration has invested in clean energy.

“It was a rigged deal as I assumed it would be,” Trump said. “The press is so dishonest in this country. It’s amazing.”

With eight weeks until the election, both sides return to the campaign trail this week, targeting swing states as the race enters its final stretch. However, it remains to be seen whether the debates will shift votes in what has virtually been a neck-and-neck contest for months.

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Presidential candidates who have lost their first debate but have also gone on to win elections include George W Bush in 2004, Barack Obama in 2012 and Trump in 2016.

“Whatever people thought about the debate, it’s not the first or last thing they’re going to see, read or hear about when it comes to Harris or Trump,” said veteran Republican consultant Chris Nicholas.

“She did a fairly good job, he wasn’t very good and the moderators were fairly tilted [in Harris’ favour]. But whatever new information voters picked up doesn’t exist in a vacuum.”

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