The second presidential debate weakened former Vice President Joe Biden’s standings, “Fox News Sunday” host Chris Wallace said on “America’s Newsroom” Friday.

In stark contrast to Wednesday’s almost tepid night of discussion, Thursday night’s set of ten candidates came out swinging against Biden, who had led polling for weeks prior to the debates.

According to “Special Report” host Bret Baier on Thursday, Biden’s campaign had anticipated a fight and they released prepared rebuttals to possible attacks before the first night began.

Just hours ahead of the second debate, Biden’s campaign advisers told reporters he would use the evening to talk about "really transformational change" by stressing his belief that he can end this period of hyper-partisanship and return the country to civility.

Instead, he spent the evening on the defensive.

As a lower-polling contender—Biden’s allies had even suggested he should pick her as his running mate—Senator Kamala Harris, D-Calif., had long struggled to break out of the pack.

And, Wallace said, she seemed to hit Biden where it hurt.

“Like everybody, I thought that Kamala Harris had a great night. She lit Joe Biden up,” he told host Sandra Smith.

Wallace cited a moment where Harris threw herself into a squabble among the other candidates: “First of all, she had a great line. That would have been enough kind of to have a viral moment when she said, ‘Let’s not have a food fight. Let’s talk about putting food on the table.’”

“But then,” he added. “She went after the vice president and the frontrunner for the Democratic nomination. Both on his bragging about doing business with segregationist senators and then on busing. And, the vice president’s support back when he was in the 70s for his…support for forced busing.”

It was this direct line of questioning from Harris to Biden on desegregation busing that helped to catapult her name into the most-searched term on Google.

Desegregation busing was the practice of assigning and transporting students to schools to redress prior racial segregation of schools or to overcome the effects of residential segregation.

“I do not believe you are a racist,” she told Biden. “But, I also believe, and it's personal…it was hurtful to hear you talk about the reputations of two United States senators who built their reputations and career on the segregation of race in this country."

She continued: "And, it was not only that but you also worked with them to oppose busing. And, you know, there was a little girl in California who was part of the second class to integrate her public schools, and she was bused to school every day. And that little girl was me."

Shortly after the exchange, @KamalaHarris tweeted a photo of herself as a child to fit with her story.

“And, she pointed out that, in fact, she had been bused in the 70s as a little girl,” Wallace said. “He was opposed to it and she was saying, ‘Look, that was something that was important in terms of school desegregation’ and he didn’t answer that very well. It was something that was clearly going to be a subject that was brought up.”

Biden asserted that Harris' criticisms on race were a "mischaracterization across the board."

“We know he’s got a long record—what, 45 years in Washington as a Senator and as a vice president—and he kind of had a faltering answer,” said Wallace.

By the end, Biden stopped himself, acknowledging, “anyway, my time is up.”

Representative Eric Swalwell (D-CA) also suggested—to audible groans from the audience—that it was time to “pass the torch to a new generation of Americans.”

To which, Biden responded, “I'm still holding on to that torch.”

Wallace didn’t buy what Swalwell was trying to sell to the crowd: “I don’t think just saying you’re old and I’m young and so pass the torch—I didn’t think that was nearly as effective. And, you can see the crowd kind of was uncomfortable with that as well.”

“I think you can’t overstate it, Sandra, because the fact is that this is the first of 12 rounds of debates that are going to take place on the Democratic side. This is the first down, 11 to go,” he noted.

“But, I think in the frontier it probably weakens Joe Biden as a frontrunner and it strengthens Kamala Harris.”