Republican presidential candidate Jeb Bush speaks to voters on Feb. 17, 2016, in South Carolina, contrasting his experience with that of his opponent and fellow Floridian, Marco Rubio. | Getty Bush struggles to mask mounting frustration 'I should stop campaigning maybe,' the candidate quips.

SUMMERVILLE, S.C. — Jeb Bush is having a rough day.

Fighting for his political life in the final days of this primary battle, Bush took the stage intent on showing toughness and drawing a sharp contrast between himself and Marco Rubio. Just moments earlier, he’d gotten devastating news: South Carolina Gov. Nikki Haley, whose endorsement he’d sought, was backing Rubio, who poses the biggest threat to his own chances of political survival.


“Disappointed,” Bush told reporters, summing up his feelings about Haley’s endorsement as he was leaving the town hall here. “She’s a very good governor and should I win the nomination, there’ll be a role for her in the campaign.”

But many of the voters who attended Bush’s town hall had just laid bare their own doubts about Bush’s chances to be the GOP nominee. During the question and answer period following an unusually hot-tempered 30-minute rendition of his stump speech, Bush received unsolicited advice from three audience members in succession, each encouraging him to be tougher.

It did not improve his mood, which was noticeably tense from the get-go.

When Bush began speaking to a crowd of 150 people at a country club here, the microphone on his lapel didn’t work. “I can’t do anything about it,” he snapped at someone in the crowd who said they couldn’t hear him. “I’ve got to keep on talking.”

Grabbing a hand-held microphone from a staffer, Bush barreled ahead, showing uncharacteristic flashes of emotional intensity as he responded to the assertion by Rubio, his former protégé, that he lacks foreign policy experience.

“It’s hard for me to be lectured by a gifted young guy who thinks going to a committee hearing means you think you know something about the world,” Bush said after ticking off the three bills Rubio touts as his Senate accomplishments and dismissing them as inconsequential.

Bush made the same pointed attack on Rubio at his first town hall earlier Wednesday in Beaufort, asserting that he knows better than Rubio “what it is to be commander in chief.”

“For someone who has no experience at all to suggest I don’t — having lived overseas, having worked overseas, developing relationships with leaders overseas, being governor of the fourth-largest state and being a commander in chief of the Florida National Guard,” Mr. Bush said. “With all due respect, Sen. Rubio, your four years or five years, or whatever it is as senator, does not match up to my capabilities of understanding how the world works.”

Bush, who polls show is slightly behind Rubio with four days left here, has sought to make South Carolina’s first-in-the-South primary a commander-in-chief test in a state with a large number of active-duty military and veterans. But he’s struggled to break into the news cycle, dominated once again by Donald Trump, who managed to upstage even the first campaign appearance here Monday by former President George W. Bush, and by Ted Cruz, whom Trump has threatened to sue.

“The press is totally at the mercy of Donald Trump,” Bush said after Edward Scott, 58, a Bush supporter, stood up and expressed concern that the former governor’s pitch on preparedness and policy “doesn’t resonate” and that the bombastic businessman has been “knocking [him] off center.”

Moments later though, a second likely Bush supporter, David Villinger, 62, stood up and offered a similar lament that his campaign “has been co-opted by the P.T. Barnum of our time.”

Then a third questioner encouraged Bush to show more fire, asking Bush if he could be more of “an [S.O.B.]” like his brother.

“I’m the only one standing up to the bully,” Bush shot back at Scott. But many in this audience, although they’re supporting a candidate they still believe would make the best president, worry that it might be too late.

“He may be doing it, but I’m not seeing it,” Villinger told reporters after the event, just a few steps from where Bush was posing for pictures. “I only see what’s on the television every day.”

The questions, especially following one of Bush’s more impassioned town hall performances to date, served to underscore his predicament in South Carolina and the broader GOP nomination fight.

Bush is in serious danger of seeing his support dry up if he cannot at least finish ahead of Rubio, another candidate with appeal to the mainstream Republicans who are seeking a single standard-bearer to consolidate behind before Trump, or perhaps Ted Cruz, runs away with the GOP nomination.

For months, Bush has shied away from harshly attacking Rubio after his first attempt to do so on the debate stage in late October backfired badly and sent his campaign reeling. Now, however, there is little to lose — and Bush was sure to remind voters here that he was responding to Rubio’s questioning of his foreign policy experience.

“This isn’t negative,” he said.

But after bulldozing through 30 minutes of remarks, Bush struggled to mask his own frustration as he asked the audience to vote for him Saturday in words that were dripping with gallows humor.

“It’s all been decided, apparently,” Bush said. “The pundits have already figured it out. We don’t have to go vote. I should stop campaigning maybe.”