Jeb Bush Says His Campaign Is 'Not on Life Support' After his performance in last night's debate, Bush said he's doing fine.

Portsmouth, New Hampshire -- Last night was not Jeb Bush’s night. After high hopes for a strong performance in Wednesday's debate, Bush allowed himself to be bested by his former protege, Sen. Marco Rubio. Today, in his first post-debate appearance, he maintained that his campaign is not on its last leg.

"It’s not on life support," he said of his campaign. "We have the most money, we have the greatest organization. We’re doing fine."

This weekend, speaking to a group of donors in Texas, Bush assured them that he would electrify in the third debate. Instead, he was widely seen as one of the losers, speaking for little time and not delivering any knockout blows. In New Hampshire, he downplayed his performance, maintaining that he still sees himself as the most qualified to be president.

"Look there are two types of politicians. There are the talkers, and there are the doers. I wish I could talk as well as some of the people on the stage, the big personalities on the stage. but I’m a doer.”

Though his GOP rivals were never mentioned during his remarks to voters gathered at Geno’s Chowder House, he couldn’t escape questions from reporters asking him about his debate sparring last night over Rubio’s missed votes.

"I think that people when they get elected to serve, they ought to serve," Bush said. "That’s a simple point I’m making.”

Last night, Rubio was asked by host Carl Quintanilla if he should resign from his job as Senate, following an editorial from Florida paper, the Sun Sentinel, calling on Rubio to “resign, not rip us off.”

“I read the editorial with great amusement, it’s actually evidence of the bias that exists in the American media today,” Rubio responded.

Bush then interjected, naming himself as a constituent of the senator’s.

“He’s a gifted politician. But Marco, When you signed up for this, this is a six-year term. You should be showing up to term. Literally, the senate, what is it like a French work week? You get three days where you have to show up. You can campaign. Just resign and let somebody else take the job,” Bush said.

Members of Congress missing votes is an oft-cited concern of Bush’s out on the campaign trail. But this time Rubio, who has avoided criticizing Bush on the trail, was prepared with an answer.

“The only reason you're doing it now is because we're running for the same position," he said. "Someone convinced you attacking me is going to help you. Here’s the bottom line, my campaign is going to be about the future of America it’s not going to be about attacking anyone else on this stage.”

Today, Bush said that his biggest problem with the debate last night was the subject matter of the questions. CNBC billed the debate as a debate of the economy; many within Bush’s camp saw it as a prized opportunity for Bush to talk policy, as fiscal issues lay at the crux of his campaign.

"There wasn’t any substantive question that were the questions that people talk about around their kitchen table. Very few things that were real, it was all about the horse race. It was all about the, trying to figure out the gotcha question to make people look bad,”Bush said.

And within his camp, many privately seethed about the time he was allotted. His campaign manager, Danny Diaz told ABC News, “We were afforded very little time and highlighted it.” An aide added that it was “a poorly managed debate.”

But today, even as donors privately fret about their man’s performance and staffers fume over missed opportunities, Bush says that it’s not over yet, overtly attempting to maintain the “joyful” spirit that his campaign has long proclaimed it embodies.

Asked if he projects enough strength to be president, he chuckled. "We’re going to find that out aren’t we?"

"End is not near,” he said, adding, "Life is good."