Can Donald Trump be stopped?

The long Republican campaign was condensed into two hours during last week's fractious presidential debate: Donald Trump sailed above the other candidates, who mostly engaged in round-robin fighting that left each of them wounded and him largely unscathed.

As a result, the debate, the sixth in a nomination contest that has defied predictions, left a GOP establishment that fears disastrous repercussions from a Trump nomination no closer to finding a way to head him off, with the first balloting now just two weeks away.

Trump repeatedly dismissed the nuanced arguments of his peers in favor of the blunt and forceful assertions that have made the billionaire the party's national front-runner.

Declaring that "I will gladly accept the mantle of anger," he made clear that he understands what many of his establishment foes still seem not to — that much of what they see as weaknesses in his campaign are the wellsprings of its support. But in this debate, he also sanded some of his sharp edges with humor and worked to humanize himself.

His opponents, by contrast, often acting with visible desperation to attract attention as voters start making up their minds, seemed mostly intent on fighting among themselves. That precluded any single candidate from rising above the others.

Texas' Sen. Ted Cruz, tied with Trump in first-voting Iowa, tried to take on the businessman repeatedly but found his complaints dismissed. He was himself pummeled by other candidates who want to replace him as Trump's main nemesis.

Florida's Sen. Marco Rubio, in particular, clashed angrily with Cruz over their positions on immigration and taxes.

He and Cruz emptied their opposition research files onto each other, with Rubio at one point moving from criticism of Cruz's positions on immigration and crop insurance to accuse the Texas senator of having once called Edward Snowden, the former National Security Agency contractor who leaked U.S. secrets, "a great public servant."

"Edward Snowden is a traitor. And if I am president and we get our hands on him, he is standing trial for treason," Rubio said.

Republicans typically pick as their nominee the person who placed second the last time out, but this race has been nothing the party has seen before. The second-place finisher last time, former Pennsylvania Sen. Rick Santorum, has done so poorly that he was relegated to the three-candidate opening debate.

Instead, it is Trump who has controlled the race. An NBC News/Wall Street Journal poll last week showed him in first place nationally, with the support of 33 percent of Republican primary voters. Cruz was second at 20 percent, Rubio at 13 percent and Ben Carson at 12 percent. Nobody else was in double digits.

The survey also showed a dramatic shift in Trump's direction on another important measure. In March, 23 percent of GOP primary voters said they could see supporting him. Now it's 65 percent.

Trump's debate presence has improved as the campaign has worn on; on Thursday, as he has in more recent debates, he seemed to shrug off many criticisms as if telling voters they should as well.

He has not just survived six debates, but started to shine. Last week, he added substance to his trademark charisma to defend his own attacks on China, embrace criticism that he's appealing to voters' anger and fend off attacks from rivals across the stage.

Cruz attempted to take on Trump when he defended an assessment days ago that Trump represented "New York values." Trump came back with a defense of his hometown that cited the world's appreciation for the city after the Sept. 11, 2001, terror attacks. It was Trump's highlight of the night — and perhaps of the entire debate season.

"When the World Trade Centers came down, I saw something that no place on Earth could have handled more beautifully, more humanely, than New York," Trump said. "We rebuilt downtown Manhattan, and everybody in the world watched. And everybody in the world loved New York and loved New Yorkers. I have to tell you, that was a very insulting statement that Ted made."

Trump's answer earned applause from the debate audience at the North Charleston Performing Arts Center in South Carolina, and also on social media, where it ranked as the night's second most tweeted moment.

"This was Trump's best moment, and this is his best debate," Wehner said. "People will remember the Trump answer, with even Cruz applauding his answer."

Ron Kaufman, the Republican national committeeman from Massachusetts, said Trump was trying to solidify his support from the conservative base of the party.

"That was a skillful way to bludgeon Cruz; it was very well done," said Kaufman. "He was as calm as I've seen him."

Trump seemed more prepared than he had in other debates and "blew it out of the park" with his answer on New York, said Reed Galen, a GOP strategist who was deputy campaign manager for John McCain's presidential bid.

"I never thought I'd say this, but I think I'd give him most improved," he said. "Hoping that he was going to implode? We've been waiting six months for that. And I wouldn't expect that he'll be less prepared next time."

Even the emotional disputes between Cruz and Rubio illustrated the difficulties of breaking out of the pack. As Rubio tried to press an argument against Cruz, he ran into a competitor for the establishment mantle, New Jersey Gov. Chris Christie, who silenced him with an arch put-down. "No, you already had your chance, Marco, and you blew it," Christie said.