Rep. Zoe Lofgren, D- Calif., said Trump became "frustrated" when briefed on his slim chances to win the election and began to shake up his campaign's legal team.

Trump's former campaign manager Bill Stepien said Trump's unhappiness "paved the way" for Rudy Giuliani to become more influential in the post-election strategy to spread false claims of widespread fraud.

"There were two groups," Stepien said. "We called them my team and Rudy's team. I didn't mind being categorized as 'Team Normal' as reporters started to do at that point in time."

Trump's White House lawyer Eric Herschmann told the committee he thought the arguments being made by Giuliani, Sidney Powell and others were "nuts."

Chris Stirewalt, a former Fox News political editor who was fired after defending his decision to call Arizona for Joe Biden, explained the 'red mirage' phenomenon to the committee: how a GOP lead on same-day voting was expected to shrink as Democrat-leaning absentee and mail-in votes were counted.

"Basically, in every election, Republicans win Election Day, and Democrats win the early vote," he explained. "So, every election, certainly in a national election, you expect to see the Republican with a lead, but it is not really a lead."

Stepien, in videotaped testimony, recalled briefing the president on the "red mirage" phenomenon, adding, "I always told the president of the truth."

"I told him it was going to be a process," he said. "We will have to wait and see how this turns out. Just like I did in 2016, I did the same thing in 2020."

Stepien also recalled a meeting with Trump and attended by House GOP Leader Kevin McCarthy in the summer of 2020, where they tried to persuade Trump to encourage supporters to vote by mail, but, "The president's mind was made up," Stepien said.

-ABC News' Benjamin Siegel

Chairman Bennie Thompson played a video compilation of witnesses describing the scene at the White House on election night after Fox News called Arizona for Joe Biden, using testimony from Trump's daughter Ivanka, campaign manager Bill Stepien, and attorney Rudy Giuliani.

Ivanka Trump told the committee in her videotaped deposition she didn't have a "firm view" of what Trump should have said the night of the election.
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Stepien told the committee he recalled Rudy Guiliani "was looking to talk to the president" and said that Trump "disagreed" with the assessment that he should not declare victory right then.

Jason Miller, a Trump campaign spokesman, told investigators that "the mayor was definitely intoxicated" and recalled that he was pushing for Trump to declare victory.

"Effectively, Mayor Giuliani was saying we won it," Miller said, "and essentially that anyone who didn't agree to that was being weak."

An attorney for Giuliani subsequently denied that he was drinking alcohol at all that night and said that the committee didn't ask Giuliani about this claim at all during his own testimony before them. "He didn’t drink alcohol that evening, only Diet Coke. He doesn’t know why Jason Miller would make that false claim," his lawyer, Bob Costello, said in a statement to ABC News.

Vice chair Liz Cheney, hitting on the point raised by Miller, added, "President Trump rejected the advice of his campaign experts on election night, and instead followed the course recommended by an apparently inebriated Rudy Giuliani."

ABC News' John Santucci contributed to this report.

"It was far too early to be making any calls like that," Trump's former campaign manager Bill Stepien told the committee in his video deposition. "Ballots were still being counted, ballots were still going to be counted for days."

Ivanka Trump also told the committee that it was becoming clear the race would not be called that night.

"To the best of my memory, I was saying that we should not go with declare victory until we had a better sense of the numbers," former top Trump aide Jason Miller said in his videotaped interview.

Stepien and Miller said it was former New York City mayor Rudy Giuliani who pressured Trump to claim victory. Miller alleged that Giuliani was "definitely intoxicated" at the time, which Giuliani's attorney, Bob Costello, subsequently denied in a statement to ABC News: "He didn’t drink alcohol that evening, only Diet Coke. He doesn’t know why Jason Miller would make that false claim."

The committee aired a snippet of Trump's speech on election night, in which he told the crowd: "We were getting ready to win this election. Frankly, we did win this."

ABC News' John Santucci contributed to this report.