When the punch landed, Jeb Bush seemed to reel. Hands folded in front of him, he opened his mouth, but no words came out. Then the moment passed.
Will history reflect that instant in last week's Republican debate as the beginning of the end of the former Florida governor's presidential campaign? Some strategists say it's possible.
That sounds dramatic, but Bush, once the presumed favorite for the GOP nomination, had fallen to fifth or sixth place in national polls even before the debate. He recently cut staff and expenses and tried to reassure skittish donors.
In the debate, Bush tried to attack Florida Sen. Marco Rubio, a former protégé, now a competitor, over Rubio's absences from Senate votes. Rubio noted that Bush had not complained about previous senators, such as John McCain, missing votes during a presidential campaign.
"The only reason why you're doing it now is because we're running for the same position, and someone has convinced you that attacking me is going to help you," Rubio said.
Pow! Bush was stunned into silence.
The next day outside Geno's Chowder & Sandwich Shop in Portsmouth, N.H., Bush defended his campaign. "It's not on life support," he said. "The end is not near. Memo to file."
But it's obviously not a good day when you have to assert you are alive.
Bush has often seemed out of his comfort zone on the trail, puzzled by a Republican Party that has shifted much further right than when he last faced Florida's voters in 2006, let alone when his father and brother were elected president.
His core message - that he is a "doer" who can fix what's wrong with government - puts him at odds with the many GOP primary voters flocking to candidates who talk about smashing the system, not fine-tuning it.
"There's a large swath of voters reacting to cultural and economic globalization in a very visceral way," said Republican strategist Bruce Haynes, president and cofounder of Purple Strategies. That's roughly half the primary vote, and it's going to Donald Trump and retired pediatric neurosurgeon Ben Carson for now.
In this political environment, Bush's eight years of experience as governor of the nation's then-fourth-largest state and deep family ties to the party establishment have not been the assets they would have been in other cycles. Republican primary voters tell pollsters, by better than 2-1, that they value "new ideas and a different approach" over experience and a proven record.
They also seem to want a fighter.
Like everyone else in politics, the Bush campaign was surprised by the Trump and Carson phenomena. The governor was not going to contend for the evangelical voter bloc fought over by candidates like Sen. Ted Cruz of Texas, former Arkansas Gov. Mike Huckabee, and former Sen. Rick Santorum of Pennsylvania.
Tea-party and libertarian Republicans have never looked fondly on the Bush family. The problem for Jeb Bush is that the field is crowded with plausible alternatives for the establishment vote: Ohio Gov. John Kasich, Gov. Christie, and, most of all, Rubio.
"Jeb hasn't distinguished himself from the others in a meaningful way," Haynes said.
Bush has repeatedly said he is planning for the long haul and has called himself a "joyful tortoise," but it sometimes seems as if he is annoyed by the topsy-turvy and often negative political climate, such as when Trump needles him as "low-energy."
"Jeb's body language is bad; he looks like he doesn't really feel like running," said one Republican strategist, speaking anonymously in order to be candid. "People see that."
Three days before the debate, Bush gave voice to his frustration.
"If this election is about how we're going to fight to get nothing done, then . . . I don't want any part of it," Bush said. "I've got a lot of really cool things I could do other than sit around, being miserable, listening to people demonize me, and me feeling compelled to demonize them. That is a joke. Elect Trump if you want that."
Many prominent Bush backers are not panicking yet, though some acknowledge major donors could bail if the campaign does not improve. Bush still has enviable strengths, including a super PAC that has $100 million or more, far more than any rival.
"Bottom line, early campaigns are up and down," said Renee Amoore, a Montgomery County businesswoman, deputy chair of the state GOP, and a Bush fund-raiser. "You'll have people dropping out, and the race will get more defined. He has too much invested. He won't quit."
On a conference call with supporters Thursday, Bush acknowledged that he needed to do better, Amoore said.
"He's a guy who's about policy, about solutions and getting things done," she said. "He has a difficult time expressing himself in the debates. What he wants to do doesn't come through in that confrontational atmosphere."
To former Pennsylvania Gov. Tom Ridge, Bush is in part a victim of expectations the candidate had no part in setting - that winning the race would be easy.
"Frankly that was an unreasonable and unfathomable belief," Ridge said. "You see the powers of the personalities in this race."
Still, Ridge says he believes that Bush will break through when the noise dies down and that his experience will become more of an asset as Republicans seriously consider their votes in the early nominating contests.
"Some people in this campaign misunderstand his style and personality, and they draw the wrong conclusions about who he is," Ridge said. "Jeb is not one to raise his voice. He's intelligent, highly focused on results. He's consistent."