During the first GOP presidential debate, Fox News anchor Megyn Kelly asked Donald Trump about his insulting remarks toward women over the years. Here are five examples, from Rosie O'Donnell to Brande Roderick. (Sarah Parnass and Nicki DeMarco/The Washington Post)

Republican leaders who have watched Donald Trump’s summer surge with alarm now believe that his presidential candidacy has been contained and may begin to collapse because of his repeated attacks on a Fox News Channel star and his refusal to pledge his loyalty to the eventual GOP nominee.

Fearful that the billionaire’s inflammatory rhetoric has inflicted serious damage to the GOP brand, party leaders hope to pivot away from the Trump sideshow and toward a more serious discussion among a deep field of governors, senators and other candidates.

They acknowledge that Trump’s unique megaphone and the passion of his supporters make any calculation about his candidacy risky. After all, he has been presumed dead before: Three weeks ago, he prompted establishment outrage by belittling the Vietnam war service of Sen. John McCain (R-Ariz.), only to prove, by climbing higher in the polls, that the laws of political gravity did not apply to him.

Still, Trump’s erratic performance during and after the first Republican presidential debate last week sparked a backlash throughout the party Saturday and a reassessment of his front-running bid. The final straw for many was Trump’s comment on CNN late Friday that Fox moderator Megyn Kelly had “blood coming out of her eyes, blood coming out of her wherever.”

Sen. Lindsey O. Graham (S.C.), a fellow candidate, said Trump was jeopardizing the GOP’s chances of winning back the White House and urged party leaders to stop “tiptoeing” around him.

“I think we’ve crossed that Rubicon where his behavior becomes about us, not just him,” Graham said in an interview.

“Donald Trump is an out-of-control car driving through a crowd of Republicans, and somebody needs to get him out of the car,” Graham said. “I just don’t see a pathway forward for us in 2016 to win the White House if we don’t decisively deal with this.”

Trump — whose strident opposition to illegal immigration helped him amass a 2-to-1 polling lead over his nearest GOP rivals — was characteristically defiant and confident in a series of phone calls Saturday with The Washington Post. He vowed to reboot his campaign amid a staff shake-up and said he could capture the White House because “millions of people everywhere” who feel alienated by the political class are standing by him.

“I have a lot of money, and I’m not getting out. I’m going to win,” Trump said. “You watch: When this campaign is over, I win. As good as I’m doing — and I’m leading the polls — it’s just the start.”

Trump added, “I want this to be serious, I really do.”

However, a consensus is forming in Republican circles that Trump’s eruption over Kelly and other Fox News anchors makes his campaign anything but serious.

We've heard the top ten GOP candidates talk. Here's what happens now.

“The fire still burns, but the fire is now contained,” said Alex Castellanos, a veteran GOP strategist. “He can’t grow. He has condemned himself to be a protest candidate, not a serious candidate for the Republican nomination. That means we now move forward to a more normal debate.”

The first primary debate on Fox attracted a record cable television audience of 24 million viewers and lent some clarity to a presidential race that has seemed hazy. It underscored former Florida governor Jeb Bush’s inability, at least so far, to excite the party’s grass roots and step fully into the role of the alpha candidate. It also marked the emergence of back-of-the-pack candidates, including Ohio Gov. John Kasich and former technology executive Carly Fiorina, as potential contenders.

The performances renewed the belief of many Republican leaders that the party has the strongest field in a generation, with several contenders capable of challenging Democratic front-runner Hillary Rodham Clinton at a time when she appears increasingly vulnerable.

“What could come out of this debate is Republicans beginning to have a conversation about the ticket,” said Matthew Dowd, a former strategist for President George W. Bush. He said there was considerable chatter on Friday about pairing Kasich and Sen. Marco Rubio: old and young, white and Latino, executive and legislator, swing-state Ohio and swing-state Florida. “Maybe that’s the ticket.”

But first, the party has to move beyond Trump, who created another controversy in a Friday night interview on CNN. He hurled insults about Kelly, including the blood comment, which was widely interpreted as a reference to menstruation.

Trump’s words cost him a speaking slot at the RedState Gathering, an influential conservative event this weekend in Atlanta, and drew condemnations from Jeb Bush, Wisconsin Gov. Scott Walker and other candidates. Two notable exceptions were Rubio and Sen. Ted Cruz of Texas.

“I’ve made a decision here with Donald Trump, you know, if I comment on everything he says, my whole campaign will be consumed by it,” Rubio told NBC News’ “Meet the Press.”

In New York, meanwhile, Trump’s campaign was in turmoil as he parted ways with longtime adviser Roger Stone after weeks of quarreling over political strategy. Stone is the second top Trump adviser to leave in as many weeks.

The timeline and reason for Stone’s departure were under dispute. Trump said in an interview that he “fired” Stone on Friday night because he didn’t want “publicity seekers” working for his campaign and because he heard from other associates that Stone had been grumbling about Trump’s behavior and refusal to heed his advice in the debate.

But Stone said in an interview that he had quit and was not fired. In a resignation letter to Trump obtained by The Post, Stone expressed regret for ending a “close relationship” that dates to the 1980s but said that “current controversies involving personalities and provocative media fights have reached such a high volume that it has distracted attention from your platform and overwhelmed your core message. . . . I can no longer remain involved in your campaign.”

Trump said he dispatched his campaign manager, Corey Lewandowski, to reach out to dozens of early-state operatives and conservative leaders nationwide this weekend with the goal of expanding Trump’s nascent political organization.

“I’m going to surround myself only with the best and most serious people,” Trump said. “We want top-of-the-line professionals.”

Trump said he would not apologize for his remarks about Kelly, which he said were misinterpreted. “Only a deviant would think I was saying anything about blood somewhere other than her eyes or her nose,” he said.

Trump had been scheduled to fly to Atlanta on Saturday to address RedState, but leader Erick Erickson revoked his invitation late Friday night. Erickson — a conservative commentator with his own history of poking the GOP establishment and derogatory remarks about women — said Trump crossed a line of decency with his comments about Kelly.

Trump’s campaign responded by calling Erickson “a total loser.”

In an interview Saturday, Erickson said Trump’s remarks about Kelly — a favorite of conservatives and a colleague of his at the network where he works as a contributor — woke up the “sleeping giants” within the conservative movement.

“It’s been building for a while,” he said. “You’ve had a lot of people, myself included, holding our breath as he kept talking and talking.”

Even without being in Atlanta, Trump dominated the conference on Saturday. One after another, presidential candidates were asked to respond to Trump’s comments. On stage, Erickson described the hundreds of e-mails he had received that morning from Trump supporters calling President Obama “the n-word” and Kelly “the c-word.”

From the audience — the kind of grass-roots activists primed to rally to Trump’s anti-Washington call — there was a jarring burst of anger against the candidate.

“Talking about blood and a woman — it was just inappropriate,” said Myra Adams, 60. “Megyn Kelly is just so well-liked by the public. . . . He should have made nice-nice with her. I thought that [debate] question was a little off-base, but he took a mosquito bite and turned it into a skin cancer.”

Jeb Bush, whom Erickson introduced with effusive praise, commended the decision to disinvite Trump and called on the developer and reality TV host to apologize.

“Do we want to win?” Bush said. Or, he asked, “Do we want to insult 53 percent of all voters? What Donald Trump said is wrong.”

Katie Packer Gage, a strategist who advises Republican candidates on appealing to female voters, said that Trump poses dangers to the party at large. “People see this as a blustery, bullying circus act,” she said. “The longer it goes on, the more it becomes part of the GOP narrative.”

Strategists predicted that Trump’s raising of his hand in the opening minutes of Thursday’s debate to rule out an independent candidacy should he fail to be the GOP nominee could limit his ability to expand beyond his base of angry, anti-establishment voters. An adviser to a rival campaign described Trump’s move as “the hand of heresy.”

“If you start to see erosion of Trump’s numbers, it could become a tailspin quickly, and it could be hard to pull the plane out of the dive,” said Phil Musser, a GOP consultant and chairman of IMGE, a digital media agency. “There would be a major pile-on and likely a spectacular crash.”

Costa reported from Atlanta. David Weigel in Atlanta contributed to this report.