UPDATE: Donald Trump still insists he won the 2020 presidential election, even though he told a podcast host last week that he “barely lost.”

ABC News’ David Muir asked Trump about the comment, comparing it to his long-standing, unsubstantiated claims that the 2020 election was rigged. The former president, however, said he must have been sarcastic. Muir, however, said he had lost the sarcasm of the remark.

Trump then went into a lengthy tirade about the 2020 election, insisting that there were irregularities in some swing states before taking a stand and saying, “This is nothing new.”

Harris then said: “Donald Trump was fired by 81 million people … and he’s obviously having a hard time processing that.”

PREVIOUSLY: Kamala Harris largely stuck to her explanation of why her positions have changed on issues such as fracking, the border and immigration.

Harris said her values ​​have not changed even as her politics have changed, as she said in an interview with CNN’s Dana Bash last month.

PREVIOUSLY: ABC News’ David Muir checked some facts, particularly the wild claim that migrants in Springfield, Ohio, have been eating cats and dogs and that pets have gone missing.

The allegation is unfounded and even Trump’s vice presidential candidate JD Vance admitted that it was unverified.

Muir noted that ABC News contacted Springfield’s city manager and said there was “no evidence of this.”

“The dogs were eaten,” Trump insisted.

PREVIOUSLY: Kamala Harris embarrassed Donald Trump with one of her remarks – that his supporters ended up leaving his rallies early because they were “bored.”

She said people should attend one of his rallies and see that “the only thing you won’t hear him talk about is yourself. You won’t hear him talk about your needs, your dreams and your desires.”

He responded by denying it, falsely claiming that no one comes to her rallies. And if someone does come, he said, “she brings them on the bus and pays them to be there.”

PREVIOUSLY: Kamala Harris looked directly into the camera while answering questions – she was speaking to the audience and not just to the moderators.

“He ended up selling American chips to China to upgrade and modernize the military. He betrayed us,” Harris said of his policy toward China.

She sharply criticized Trump for thanking President Xi Jinping for “what he did during Covid.”

“We know that Xi was responsible for not giving us transparency about the origins of Covid,” she said.

Trump insisted that his tariffs would cause China to pay more for goods.

PREVIOUSLY: Kamala Harris and Donald Trump opened their debate with Harris shaking hands.

The Vice President walked up to Trump, extended her hand, and they politely exchanged greetings.

The opening question turned to the economy, with Harris sharply criticizing Trump for proposing sweeping tariffs. She said it would amount to a general sales tax on Americans because the cost would be passed on to consumers. Trump denied it was a tax before moving on to criticizing the Biden administration over the border.

“They are destroying our country,” he said of undocumented immigrants.

The stakes in this debate are enormous: Harris and Trump are neck and neck in the polls, and this event could be their only comparison this cycle.

Amazingly, Harris and Trump had also never met in person. The closest opportunity they could have met – during the transition from one administration to the next on January 20, 2021 – never happened because Trump refused to attend.

ABC News’ David Muir and Linsey Davis will moderate the debate, their first time hosting such a general election event.