On Tuesday, Jeb Bush talked to NBC News about the state of the 2016 presidential race and his plan to reinvigorate his campaign with a strong showing in South Carolina. A key part of the Jeb comeback, he suggested, was the endorsement of South Carolina’s Republican governor, Nikki Haley. “She is the probably the most meaningful endorsement there is,” Jeb said. “If she is going to give an endorsement it would be the most powerful, meaningful one in the state.” Asked what would happen if that endorsement went to someone other than him, Jeb said he would just have to “work harder” leading into Saturday’s primary.

You can probably see where this is going. On Wednesday, Haley endorsed Marco Rubio, which is as good a sign as any that the party is starting to gravitate toward Rubio and away from Bush (and, notably, the Bush family). Coming out of New Hampshire, it looked like Jeb might have had a chance to scrape something together in South Carolina: he finished (barely) ahead of Rubio in fourth place, he had South Carolina Sen. Lindsey Graham on his side, and brother George (who won the state’s primary in 2000) was coming of political exile to stump for Jeb. But despite all that and a relatively spirited debate performance, Jeb’s been treading water in the polls while Rubio and Ted Cruz have risen in tandem to fight for second place and Donald Trump has maintained a massive lead. If Jeb can’t demonstrate that he’s a viable challenger to Rubio for establishment-minded Republicans, then he’s run out of reasons to stay in the race.

Advertisement:

But that’s no guarantee he’d quit in a timely fashion. In that same interview with NBC News, Jeb ruled out any talk of dropping out post-South Carolina.

“We’re in it for the long haul,” Jeb said, forcing himself to believe it’s true. His campaign has been repeating some variation of this line for months, explaining that they have the resources to go deep into the primary, even if nobody really wants to vote for Jeb. Their theory of the race was that as the unserious candidates flamed out, voters would coalesce behind Jeb and he’d win by attrition. Well, pretty much all the jokers have split, and Jeb’s still struggling to put together any meaningful support.

Advertisement:

Assuming he’s barreling toward the unremarkable South Carolina finish that the polls suggest he is, the question becomes how long Jeb drags this out. He’s an afterthought in Nevada, so he’ll find no solace there. And the road doesn’t look much better after that. People in Jeb World have always pointed to March 15 as the make-or-break date for all the campaigns. “March 15 is the big day,” Right To Rise PAC head honcho Mike Murphy said back in October. “On the 16th, I don’t think anybody will have a mathematical lock, but there definitely will be a very strong leading candidate.” Some big states vote on March 15, including Illinois, Ohio and (most important) Florida, all of which are winner-take-all when it comes to delegates.

It’s conceivable that Jeb could stick around until then – he’s sunk a ton of resources into banking early votes in Florida, and he may think he has a chance at staging one last defiant stand in the state that elected him governor twice. But it seems pretty hopeless. The last time Jeb led in a Florida poll was June 2015; it’s been all Trump since then while Jeb has steadily declined (he’s at 4 percent in the most recent CBS News poll).

And it’s still a month away, which is a long time for a campaign to wheeze along. If it isn’t happening already, he’s guaranteed to come under pressure from the party establishment to clear the way for Rubio to take on Trump and Cruz. If Rubio turns in a stronger performance in South Carolina than is currently expected, that pressure will be all the more intense. At that point, Jeb wouldn’t be viewed as anything more than a sea anchor hampering the prospects of a superior candidate who already faces difficult odds in taking on the Trump/Cruz insurgency.