This could be Jeb Bush's last stand

SPARTANBURG, S.C. — Jeb Bush's happy warrior mask is slipping with his back against the wall in South Carolina.

The former Florida governor's team proudly declared the state "Bush country" as the primary kicked off ten days ago, the place that would resurrect his candidacy and return some order to a universe in which a big-fundraising, well-qualified brother and son of presidents should succeed in American politics.

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Instead, he's has been met with a series of setbacks and indignities and appears on the brink of a weak finish in Saturday's election that could deal a fatal blow to his campaign. And he's not happy about it. See also: Here's who would be president if Facebook likes counted as votes

"This is a fun journey but it gets arduous from time to time," Bush admitted as he wrapped up his speech in Columbia Friday afternoon after asking for voters' prayers — whether or not they're backing his campaign.

Bush hoped his edging Marco Rubio for fourth place in New Hampshire would give him a badly needed boost with the South Carolina voters who helped put former President George W. Bush on the path to the GOP nomination in 2000. He even got his older brother out on the stump for the first time, putting a renewed bounce in his step.

But the voters have proven slow in following. A highly coveted endorsement from popular South Carolina Gov. Nikki Haley — one Bush himself had described as "the most powerful, meaningful one in the state" earlier this week — went instead to Rubio. Bush and his campaign have spent days fighting off questions about when he'll drop out with growing irritation, and denying reports that he's running out of money. And a big bet on the state doesn't seem to be paying dividends.

It doesn't look likely that Bush will do any better here than he did in the New Hampshire, with polls suggesting he's barely cracking double digits and is more likely than not to finish behind Rubio for fourth place even though his super-PAC has dropped $13 million on ads — almost as much as the other candidates and their super-PACs combined.

Bush still has a chance to beat Rubio in South Carolina, and has a tiny glimmer of hope at catching Ted Cruz for second place. He's not that far behind either in recent surveys, and the polls have proved wrong before.

But if he does finish fourth, the chorus of establishment Republicans calling for him to exit the race and let another candidate unite the party against Trump will grow deafening. Whether or not he ignores them, his pleas to donors to keep faith become even harder — just as the campaign calendar turns to a stretch of big expensive states.

"I hope that you believe that it's possible for us to do this," a plaintive Bush told voters in Rock Hill Thursday night. "I hope you don't think the end is near."

Bush had the entire clan on the trail in the final days, bringing in his siblings, his wife and even his mother as he seeks to right the ship. And while they sought to stay upbeat, even his own family admitted that it hasn't been smooth sailing.

"These things never go the way that you hope. You have you game plan, you're going to have some bumps in the road. Donald Trump has clearly been a wildcard in this campaign. But sooner or later it's going to come down to Trump and one other guy and I still believe Jeb's going to be that candidate," Marvin Bush told Mashable after his older brother's Columbia rally. "He certainly wants to have a good showing in South Carolina, and I think he's poised to do so."

To add insult to injury, the man who just in the last few days attacked Bush's brother for failing to prevent 9/11 and publicly feuded with the pope himself looks poised to cruise to victory, with Trump holding a comfortable lead in most recent polls.

Flashes of irritation kept breaking through Bush's upbeat demeanor in the final days on the campaign trail in South Carolina.

"I've been tagged as the common core candidate. Look, you know what I am? I'm the education candidate," an exasperated Bush said Friday morning in Spartanburg after calling the rest of the candidates "jibber jabbers" who don't know squat about education reform.

"It's not a town hall unless it's like this where you get to ask questions," he snapped at one voter in Columbia who referenced a comment from Trump's town hall with MSNBC the previous night.

And he was clearly sick of how he's described in the media.

"The pundits on cable TV [say], you know, I'm in the establishment lane. It's like an interstate somewhere, you go just straight and you can't do anything about it," he groused earlier in the speech to roughly 100 people packed into a side room at a local soul food restaurant. "This so-called establishment candidate in the establishment lane turned the whole state upside down."

Even his surrogates seemed as focused on firing back at his weaknesses.

"To those who say 'we don't want dynasties,' I understand what you're saying. But there's no such thing as dynasty in America. The only way you can become president is if your fellow citizens vote for you," South Carolina Sen. Lindsey Graham said as he wrapped up his Spartanburg comments. "Jeb Bush is the best guy for the times in which we live in."

Bush had a similar reply when a college student told him his peers said they wouldn't back him "just because you're the third Bush."

"I'm not trying to break the record with the Adams family and the Bush family," he joked before pivoting away from the question.

"Know that there are a lot of people praying with you," one woman told Bush in Columbia, bucking him up by complimenting his mother before asking her question. "Don't lose heart."

But if he can't claw his way past Rubio Saturday night, it's hard to see how Bush sticks around for much longer.

Check out more from the 2016 campaign in the gallery below.

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