DES MOINES, Iowa – With a debate gaffe blasting through his presidential candidacy, Rick Perry turned from seeking resurgence to trying to avoid extinction.

His own fundraisers have begun to abandon him. Republican strategists are offering eulogies. The Texas governor, who has avoided interviews throughout his two-month campaign, signaled the depth of his desperation by talking almost nonstop to national media outlets Thursday, ending with a stop on CBS’s “Late Show With David Letterman” to mock his mistake. Few thought it would help.

The candidate who shot to the top of the polls as the alternative to Mitt Romney, only to plummet earthward from a series of mistakes, now faces multiple conundrums. The stakes for all future debates — the next is Saturday — loom as huge even though Perry acknowledges obvious shortcomings in that setting. His political fate rests on a win in Iowa, but he now faces competing pressures to camp out there and to travel the nation raising money.

Perry campaign staffers attended what one official described as “an upbeat meeting” in the campaign’s Austin headquarters Thursday morning. But the buoyant message from Austin masked deep concern among some of the campaign’s most ardent allies.

The tumult stemmed from an exchange in Wednesday’s debate in Michigan. Perry said once elected he would eradicate three departments to shrink the federal government. After naming two — Education and Commerce — he drew a blank on the third. After an agonizing period of time, during which his rivals tried to help him out, a dazed-looking Perry finally gave up.

“I can’t,” Perry replied. “The third one, I can’t. Sorry. Oops.”

Later in the debate, he remembered the department — Energy — which governs an issue he talks about constantly at campaign events.

The exchange was especially devastating because it reinforced growing perceptions among Republicans that Perry lacks the deftness and discipline required to serve in the Oval Office

“It still makes my skin crawl, and I’ve watched it 37 times since last night. It was just an unbelievable mental collapse,” said Rich Galen, a veteran GOP strategist watching the primaries from the sidelines. “One of the things about being presidential is being able to react properly in a crisis. … For Perry last night that debate was a crisis mode. It was a big moment and he couldn’t do it. I don’t see how he comes back.”

During prior debates, Perry called Social Security a Ponzi scheme and said those who disagree with in-state college tuition rates for illegal immigrants “don’t have a heart.” While campaigning, he implied that Federal Reserve Chairman Ben Bernanke was edging toward treason and would be dealt with violently in Texas. He suggested the American military get involved in Mexico’s drug war. After a supporter denigrated Mormonism — Romney’s faith — as a cult, Perry had to answer for it for days.

When he turned to the roll-out of his economic plan, Perry got in his own way by questioning whether President Obama was born in the United States. Then he gave a bizarrely animated speech in New Hampshire that spurred questions about whether he was sober. He said he was.