In the GOP civil war over defunding Obamacare, the battle lines have been drawn, proverbial rifles aimed, and ultimatums issued — but what if Ted Cruz and his fellow insurgent leaders turn around to find their army has deserted?

Cruz, the Texas Republican who has led the push in the Senate to shut down the government unless the health-care law is defunded, acknowledged yesterday on CNN’s “State of the Union” that he does “not have the votes right now.” (Nowhere near it, in fact, with just 13 GOP senators out of the at least 41 needed signed up.)

“It is going to take a [grass-roots] tsunami,” he told host Candy Crowley. Then he made this astonishing admission: “Now is the single best time to stop Obamacare. If it doesn’t happen now, it’s never going to happen.”

He’s absolutely right on that, of course, as once the law’s exchanges go into place on Oct. 1, it will be procedurally and legally much more complicated to undo, not to mention that the political calculus flips once people start depending on Obamacare’s benefits.

If a “tsunami” doesn’t materialize in the next month (don’t hold your breath), then the defunders will demand heads. Republicans who vote to fund Obamacare “need to be replaced,” Jim DeMint, the former senator and current president of the Heritage Foundation, told NPR last week.

Ousting allegedly squishy Republicans — or at least using primary pressure to move them to the right — has  been the tea party’s bread and butter, after all, and it has been largely successful. And as Greg noted last week, defunding Obamacare has already become a litmus test in GOP primaries. But even that threat seems to be evaporating as the tea party struggles to find credible candidates to challenge incumbents, the National Journal’s Alex Roarty reports this morning:

There aren’t three Republican senators more vulnerable to a tea party challenge than Lamar Alexander, Lindsey Graham and Mitch McConnell – longtime incumbents with a history of deal-making and moderation that conservatives love to hate.


But conservative activists itching for primary fights are missing an essential element of victory: candidates.


In each of the three races, conservatives worry that they’ve yet to find a credible primary challenger, one capable of knocking off a better-known and better-financed incumbent. And now they fear that they’ll squander some golden opportunities in what should be a great cycle.

In Tennessee, where Republicans probably could nominate a more conservative candidate and still comfortably win a general election, Alexander’s only challenger so far is a state representative who couldn’t gain traction in an aborted bid against Scott DesJarlais, the Republican congressman who as a doctor had affairs with his patients. That leaves little hope for his Senate bid.

Kim Severson of the  New York Times has more reporting today on Graham’s challenge in South Carolina, where tea party groups have taken to calling the hawkish Republican “a community organizer for the Muslim Brotherhood.” But despite their common antipathy for Graham, the 40-plus tea party and libertarian-leaning groups in the state must first hash out “a civil war of their own,” Severson reports, as they can’t decide on a common candidate.

The most promising choice is Nancy Mace, the first woman to graduate from the Citadel, but GOP strategists say the marketing executive, who has never run for office, “might not be ready for primetime.” Indeed, running against a well-funded and high-profile incumbent like Graham will be no easy task. He’s faced the tea party’s ire since its inception — it flushed him down a toilet in 2009, at least in effigy — but so far remains largely unscathed.

Which all raises the question: With few votes in Congress and the lack of a credible outside threat, has the Tea Party tiger lost its teeth in the Obamacare fight? At some point, even John Boehner and other GOP leaders know they’re going to have to level with their base on Obamacare (it will not get defunded) and the debt ceiling (it will get raised) and government appropriations (it will get funded) — so when will they be brave enough to have that hard talk? As Cruz said, we’re running out of time.