Rick Perry said Thursday "it ain't a day for quitting nothing" after his big "oops" during the Republican presidential debate the night before.

"Oh, shoot, no," the Texas governor said Thursday morning during a series of media appearances, when asked if his debate gaffe would propel him to pull out of the race.

Perry spent the day on a media blitz trying to laugh about the Wednesday evening debate where he struggled embarrassingly to remember one of the three federal departments he wants to abolish, ending with a grinning, "Oops."

He even appeared on The Late Show with David Letterman to offer the night's Top Ten List of excuses for the debate.

"Hey, listen. You try concentrating with Mitt Romney smiling at you. That is one handsome dude," Perry chuckled during his segment with the comedian.

The minute-long exchange was replayed throughout the day and into the evening on television, and it has already been labeled one of the worst debate blunders in recent memory.

On Wednesday, Perry was on stage with main rivals Herman Cain and Mitt Romney, the frontrunner, at a university in Rochester, Mich., when the debate sponsored by CNBC turned into a comedy of errors.

Perry was discussing the three government departments he wanted to cut but forgot one of them in a major flub that left some of his supporters declaring his campaign was over.

"I'm sure glad I had my boots on because I sure stepped in it out there," Perry told the media immediately after the debate.

The debate had been predicted to be dominated by the sexual harassment allegations against Cain, a businessman and former head of the National Restaurant Association, but Cain escaped unscathed and all the focus was on Perry's gaffe.

P.O.V. Should Rick Perry end his campaign after flubbing the debate? Have your say.

The awkward moment, posted to YouTube within moments, was a reminder of the poor debate performances that have hurt the Texas governor’s once-soaring campaign and the difficulties he has had trying to hold his own on the national stage.

Still, the extended debate exchange ended with Perry's rivals trying to bail him out, suggesting the Environmental Protection Agency was the third agency he forgot to mention as being on his chopping block.

"EPA, there you go," Perry said, seemingly taking their word for it.

The biggest gaffes on the Republican campaign trail Republican presidential candidate Rick Perry The Republican campaign has been well worth following, not so much for its ideas on American governance, but as a seemingly endless stream of slip-ups.

When pressed, he drew another blank.

"Seriously?" asked moderator John Harwood, one of the CNBC debate hosts. "You can't name the third one?"

"The third agency of government I would do away with — the education, the commerce. And let's see. I can't. The third one, I can't," Perry said. "Oops."

Perry says he's not the 'slickest' debater

Later in the debate, Perry revisited the question and said he meant to call for the elimination of the Energy Department.

On Thursday, Perry said he just couldn't think of it.

"There were so many federal agencies that come to mind, that I want to get rid of, that the Energy Department would not come out," he said in an interview taped for ABC's Good Morning America.

In another interview, Perry said: "If Americans are looking for the slickest politician, the smoothest debater, I readily admit, I'm probably not their guy."

Donors to Perry's campaign were said to be nervous or panicking following his debate flub, but Perry's advisers said Thursday they already have the cash they need to run through to South Carolina.

On NBC's Today show, Perry seemed to try to make the best of the gaffe, saying that forgetting the names of all the agencies he believes should be eliminated makes the "core point" of his campaign — that there are too many agencies. He has already blasted an email out to his supporters asking them, "What part of the federal government would you like to forget about the most?" His website now asks supporters to vote for one.

'We all felt very bad for him'

The fallout from Perry's debate goof has been brutal.

"We all felt very bad for him," Michele Bachmann, the Minnesota congresswoman also running for the nomination, said, calling the moment uncomfortable.

"Rick Perry just lost the debate. And the entire election. You only had to name three," Tim Albrecht, the top spokesman for Iowa Gov. Terry Branstad, who is unaligned in the GOP race, tweeted from his personal account.

"Perry response will be on highlight reels for years to come," business legend Jack Welch tweeted.

The next few days will shed light on whether voters care about the misstep.

Over the past two weeks, Perry has sought to prove he's still a credible challenger to Romney by rolling out detailed policy proposals. But he's found himself dogged by suggestions that he had been drinking or taking drugs when he gave an animated speech in New Hampshire. It went viral online, prompting Perry to state that he was not, in fact, under the influence of a substance.

NBC's Saturday Night Live did a Perry parody last weekend that was widely viewed.

In recent days, the candidate started to take his message directly to voters by running sunny biographical television ads in early primary states like Iowa and New Hampshire. It's an effort to reintroduce himself to Republican primary voters in a safer setting that circumvents the news media.