Trump refuses to commit to 2nd debate with Harris -- saying she wants to because she lost

Former President Donald Trump has begun to shut down the possibility of a second match against Vice President Kamala Harris after debating her Tuesday night, claiming he doesn't need to debate her again because he won the debate.

"Well she wants a second debate because she lost tonight, very badly," Trump told ABC News late Tuesday night during a surprise appearance in the spin room after participating in the presidential debate hosted by ABC News in Philadelphia.

"So, we'll, you know, think about that. But she immediately called for a second," Trump said, refusing to commit whether he'd participate.

Less than an hour after the ABC News presidential debate ended Tuesday night, Harris' campaign called for another matchup. The campaign put out an email touting her performance at the debate and blasting Trump for his responses and demeanor.

Pressed by ABC News why Trump wouldn't commit if she lost the debate, Trump said he's looking at polls, boasting about what he believed is a lead over Harris in polling numbers. Harris leads Trump, 47% to 44%, according 538's polling average.

Trump's non-commitment to a second debate comes after the former president in May said he accepted what was going to be a fourth presidential debate with NBC News between Trump and then-candidate President Joe Biden -- after debates with CNN, ABC News and Fox News.

In August, after Harris took over the top of the Democratic ticket, Trump again agreed to participate in a debate hosted by NBC, after ABC News and Fox News' debates. Trump ended up doing a town hall with Fox News last week after Harris declined to participate.

But since the ABC News debate, Trump has been gradually escalating the rhetoric that he doesn't need a second match with Harris, telling Fox News' Sean Hannity on Tuesday night, "I sort of think maybe I shouldn't do it."

"I have to think about it, but if you won the debate, I sort of think maybe I shouldn't do it. Why should I do another debate?" Trump said on "Hannity."

During his visit to the Shanksville Volunteer Fire Department in Shanksville, Pennsylvania, Wednesday afternoon to honor the anniversary of the Sept. 11, 2001, attacks, Trump said he was thinking about the possibility of a second debate.

"We’re looking at it, but, you know, when you win, you don’t really necessarily have to do it a second time. So we’ll see, but we had a, I thought we had a great debate last night," Trump said. “I just don’t know. We’ll think about it.”

On Wednesday morning, Trump called into "Fox and Friends" and said he'd be "less inclined to" do a second debate with Harris. Still, he kept his options open without shutting down the possibility of a second debate completely: "Let's see what happens."

And on Wednesday afternoon, Trump posted on his social media site, "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," he continued. "She was beaten badly last night. Every Poll has us WINNING, in one case, 92-8, so why would I do a Rematch?"

538 has collected three national polls and one swing-state poll that were conducted since the debate. In all of them, more people who watched the debate said Harris won the debate than said Trump did. On average, 57% of debate watchers nationally said Harris turned in the better performance; only 34% said Trump did.

Showing up in the spin room after the debate, Trump claimed Tuesday night was his "best debate ever," suggesting his spin room visit had nothing to do with needing to clean up his debate performance.

"We thought it was our best debate ever. It was my best debate ever," Trump said to a large group of reporters that surrounded him in the spin room.

"It showed how weak they are, how pathetic they are, and what they're doing to destroy our country, on the border, with foreign trade, with everything. And, I think it was the best debate I've ever personally -- that I've had," Trump continued.

But after the debate, Lara Trump, the former president's daughter-in-law and Republican National Committee co-chair who served as the former president's surrogate in the spin room, said he had a "fine night," adding she wished there were more debates.

"I think he had a night that we expected to see, which is that Donald Trump was four years in the White House. We all remember how our lives were then," Lara Trump said when asked about Trump's performance.

Pressed by reporters if she means her father-in-law didn't have a great night, Lara Trump said, "I mean, he had a fine night," and then added: "He had a night that was absolutely necessary, and I am so happy we finally got to see these two people on the stage."

"I wish we had two more debates. We usually have three presidential debates. Kamala Harris has said -- she only wants one, so far," Lara Trump said just minutes before the Harris campaign called for a second debate. "Donald Trump would certainly be willing to do another debate."

Some Democrats on Capitol Hill said Wednesday weighed in on the prospect of another Harris-Trump debate.

Sen. Tim Kaine said he supports another presidential debate between Harris and Trump, but said he didn't think the former president would agree.

"I’m sort of not expecting that President Trump will accept a second debate, but [Harris] is very willing to do it and that’s good," Kaine said.

Asked if another debate is needed, Sen. Cory Booker said "I don't know about the word 'needs.'"

"I mean this one debate was so revelatory, it so exposed Donald Trump," Booker said. "I think it was a reminder for a lot of people just how unhinged and unchecked this guy is; how he can't control himself."

ABC News' Allison Pecorin contributed to this report.