This led to him angrily pivoting back to the US border crisis by bringing up unfounded rumours of Haitian immigrants in Springfield, Ohio, kidnapping and eating people’s pets.

“They’re eating the dogs – the people that came in – they’re eating the cats, they’re eating the pets of the people that live there!” he lamented, in what may be one of the most bizarre sets of remarks ever heard in a presidential debate.

After the moderator explained there was no proof of this having occurred, Harris laughed at Trump and said: “Talk about extreme.”

The former president had entered the debate knowing this would be one of his best shots to reverse the momentum that has shifted in Harris’ favour over the past few weeks.

Ahead of it, aides and allies had urged him to stick to policy and not engage in personal attacks that could be perceived as racist or sexist, knowing this could alienate women and the undecided voters in swing states.

Many of those voters don’t necessarily like the direction of the country under the Harris-Biden administration, but are nonetheless reluctant to put Trump back in the Oval Office.

Among those offering free advice was Nikki Haley, who recently endorsed the Republican candidate and has seemingly forgiven him for calling her “birdbrain” during the Republican primaries while he pushed conspiracy theories about Haley’s Indian heritage.

“You don’t need to call Kamala ‘dumb’ – she didn’t get this far just by accident,” the former UN ambassador told Fox and Friends ahead of the debate. “When you call even a Democrat dumb, Republican women get their backs up too. The bottom line is we win on policy.”

To his credit, Trump largely managed to avoid repeating insults he had previously made about Harris, although he came close when the moderators asked him about comments he had made questioning her racial identity.

“I read where she was not black … then I read that she was black,” Trump said. “That’s up to her.”

But the incendiary Republican could barely contain his disdain for Harris, refusing to look at her throughout the entire debate as he accused her of being the “worst vice president in history” and “destroying” the country with higher inflation and an influx of illegal immigrants.

Arguably, his best moment came at the end, as he referred to the list of things Harris said she wanted to do if she won the election and asked: “Why hasn’t she done it? She’s been there for 3½ years. They’ve had 3½ to fix the border, 3½ years to create jobs, and all of the things we talked about.”

Harris, meanwhile, began by taking to the stage and shaking hands with Trump – a man she had not met until now – and introducing herself by her full name.

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She then spent most of the debate looking at him while he spoke, as she sought to portray him as a self-serving billionaire who wanted to wind back fundamental freedoms, such as the right to an abortion.

But the very fact that she was on the stage at all is emblematic of just how much things can change in America’s unpredictable political landscape.

Indeed, the momentum has swung in Harris’ favour since Biden withdrew from the race – something I’ve seen first-hand as I’ve travelled across key battlegrounds talking to voters, and in the record-breaking fundraising hauls for the Harris-Walz campaign.

Harris got another boost minutes after the debate ended when pop sensation Taylor Swift posted on social media that she was endorsing her.

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Encouraging her 283 million followers to do their own research, Swift said she was backing Harris because “she fights for the rights and causes I believe need a warrior to champion them”.

Adding to the moment, Swift posed in a picture with her cat, a nod to the Republican vice presidential candidate J.D. Vance’s criticism of “childless cat ladies”.

Yet despite the enthusiasm surrounding Harris, polls suggest the battle is still extremely tight, just as it was before Biden’s own disastrous debate performance on June 27.

Back then, Trump led Biden by 1.5 per cent, according to the RealClearPolitics polling average; now Harris leads Trump nationally – but only by 1.2 per cent.

With eight weeks until the election – although early voting begins next week in some states – the most-watched election in the world is still anyone’s to lose.

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