Three weeks removed from his Iowa victory and now heading into the March 1 Super Tuesday contests, Sen. Ted Cruz is facing an existential crisis that could do fatal damage to his candidacy.

Sen. Marco Rubio’s campaign is often mocked for its roundabout path to the nomination, which doesn’t put much emphasis on winning any particular state. Cruz is in the opposite position: He has a very specific path that runs through a specific set of states and most of them are coming up in less than a week’s time.

The Cruz plan is a Southern strategy powered by evangelical voters. The trial run for his approach wasn’t in the South, though, but in Iowa, where he consolidated support from social conservative leaders and built a grassroots operation that turned out religious right voters to caucus. The plan from there, as explicitly articulated by Cruz’s campaign, was to win states with similarly evangelical-heavy Republican electorates — especially March 1 states like Alabama, Arkansas, Georgia, Oklahoma, Tennessee, and Cruz’s native Texas.

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“We’ve proven that we can turn out evangelicals in Iowa, and we’re going to take that model and that organization and replicate it through the states,” Cruz’s then-spokesman Rick Tyler told reporters shortly after Iowa.

But first they had to pass another test: South Carolina. The voters who showed up for the GOP race were exactly who Cruz wanted: 67% were white evangelicals according to exit polls, even higher than Iowa’s 64%. The problem was that Trump won a plurality of white evangelicals: 34 percent over Cruz’s 26 percent and Rubio’s 21 percent. That left Cruz a weak third place overall, just behind Rubio, with zero delegates to show for his effort. The trend continued in Nevada on Tuesday, where Trump won 40 percent of white evangelical voters to Cruz’s 27 percent and Rubio’s 23 percent. Close video Cruz looks to Super Tuesday Ted Cruz remains confident that his campaign has what it takes to beat Donald Trump on Super Tuesday and beyond. Ted Cruz remains confident that his campaign has what it takes to beat Donald Trump on Super Tuesday and beyond. share tweet email Embed

Cruz has also taken some heat in recent days thanks to a combined attack from Trump and Rubio over campaign ethics. Earlier this week, the senator fired Tyler, the campaign spokesman quoted earlier, after he tweeted a video falsely claiming Rubio disparaged the Bible.

Now Cruz’s entire theory of the election is thrown into question and there’s almost no time to retool before it reaches its most critical phase. Upcoming primaries like Alabama (75 percent white evangelical in 2012), Georgia (64 percent), and Oklahoma (72 percent) are made for Cruz, but Trump has momentum with the exact voters Cruz needs to win and Rubio is proving a persistent threat as well.

The Cruz campaign is well aware of the stakes and have not tamped down Super Tuesday expectations.

“We’ve been built for this day the entire time,” Cruz campaign manager Jeff Roe told reporters on Sunday.

He described Cruz’s appeal as “somebody that can beat Trump that’s built to last.”

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Hoping to diminish Trump’s evangelical support, Cruz has been blasting Trump over his formerly pro-choice views and his recent defense of Planned Parenthood, which the GOP front-runner said in the last debate did “wonderful things” for women besides providing abortions, which he opposed. It didn’t work in South Carolina, but Roe offered a glass-half-full take: “You should have seen where [Trump] started.”

The worst-case scenario for March 1 would be losing on Cruz’s delegate-rich home court of Texas, where an Emerson poll showed Cruz at 29 percent, barely leading Trump at 28 percent and Rubio at 25 percent.

view photo essay The presidential campaign: Ted Cruz The Texas senator was first to announce his bid back in March, and has since been carefully laying the groundwork for a come-from-behind primary victory.

Texas Gov. Greg Abbott gave Cruz a boost there on Wednesday by endorsing him . “Conservative values are at his core,” Abbott said in a video statement.

The senator will have a chance to make his case in Houston on Thursday at the GOP debate and his campaign has already announced his wife, Heidi Cruz, will tour the state on his behalf for three days afterwards.

The state’s rules make it possible for a candidate to win a majority of the Texas’ 155 delegates even with a relatively small plurality of the vote statewide and in individual congressional districts — meaning even a relatively small shift toward Trump or Cruz could have a massive effect.

If Cruz leaves March 1 with a trail of losses to Trump — before heading into places like Kentucky and Louisiana on March 5 and Mississippi on March 8 — the path forward will be daunting and he could face pressure from anti-Trump conservatives to step aside. To some observers, Trump’s South Carolina victory already slammed the door on his candidacy.

“Heading into Super Tuesday on March 1, it’s increasingly apparent Rubio is the only Republican left who can stop Trump,” election analyst David Wasserman wrote in a Wednesday blog post at the nonpartisan Cook Report.



Correction: An earlier version of this story misidentified the author of the Cook Report post.