DENVER - An invigorated Mitt Romney sought Thursday to use his superior performance at the first presidential debate as a springboard to build momentum for his once beleaguered campaign.

The Republican received a rousing, standing ovation from nearly 2,000 during a surprise stop Thursday at a conservative gathering, his first appearance following the debate.

"You guys are going to have to cheer here and then go out and knock on doors and get people who voted for President Obama to see the light and come join our team," an upbeat, energetic Romney said at a Colorado Conservative Political Action Committee convention in Denver.

Obama's campaign acknowledged that his performance at the debate did not compare to Romney's -- which it mocked as "Oscar worthy" -- but said the former Massachusetts governor distorted the facts of his tax plan, his support for teachers and his proposed changes to Medicare.

Romney's spokesman dismissed the criticism as "damage control," while the Republican nominee sent a fundraising e-mail to supporters with the subject "Victory is in sight." He was visibly buoyed as he headed out of Denver, laughing with aides at the front of his plane before the entourage broke into clapping and whistles as the pilot announced that the control tower commended the former governor's performance when the plane was approved for takeoff.

At the Colorado Conservative Political Action Committee meeting, Romney savored his debate victory after weeks of campaign missteps.

Flanked by four of his five sons, Romney launched into a detailed look at his philosophy, saying the debate offered "two very different visions for the country." Obama, he said, offers "trickle-down government," which leads to tax increases and job loss. If the U.S. continues down that path, Romney said, "there's no question ... the middle class will continue to be buried with higher and higher expenses for gasoline, for food, for utilities, for health insurance."

He ticked off a list of other ideas: More domestic energy production, more cuts in government spending, fewer defense cuts.

'Continued the momentum'

State Sen. Kevin Grantham of Canyon City, who attended the gathering, said Romney "certainly continued the momentum from last night. When a candidate exudes confidence and leadership like that, he generates a certain enthusiasm."

Romney's challenge, with less than five weeks until Election Day, is to convince voters that the steady and decisive competitor who showed up for the debate is the real Romney.

The Romney whom viewers saw is not the candidate they've come to know through many months of attack ads and replayed gaffes.

Amplify his argument

The GOP nominee's team labored Thursday to ensure that his debate triumph was not fleeting, hoping that it could serve as a jolt to his flagging campaign. As one adviser said, "The afterglow will be short-lived."

Romney is rolling out a new batch of ads in battleground states, focused on taxes and jobs, that amplify his core argument from the debate: that the country cannot afford another four years of an Obama's presidency and must choose a new path.

Aides said that in coming days, Romney won't merely condemn the $5 trillion in new federal debt amassed during Obama's term, but also trumpet forecasts that the debt would grow to $20 trillion by the end of a second Obama term.

Advisers said forthcoming ads, as well as public appearances by the candidate and his surrogates, will seek to reinforce Romney's readiness to be president, something that Democrats and some Republicans had questioned in recent weeks.

The strategy calls for Romney to highlight his connection to "real folks" by sharing anecdotes about voters he has met on the campaign trail. A greater effort will be made to radiate the confidence of someone prepared to sit in the Oval Office.

Even as he finds his footing on the economy, Romney plans to give a major foreign policy speech on Monday at the Virginia Military Institute in which he is expected to challenge Obama's leadership in the Middle East.

"He needed a moment where the door was cracked open and now he's got to put his shoulder to it and go through," said Terry Holt, who was a strategist on George W. Bush's campaigns. "People want to see Mitt Romney roll up his sleeves and show how he will go to work. This is an opening, but it will take a steady, determined and focused effort to get this narrative back on firm footing."

At campaign headquarters in Boston, advisers held briefings with supporters and allies to hammer their message that the election will be a choice between two different paths for the nation, while playing down any expectations of an immediate shift in the race. "I don't think it's going to be decided by debates alone," said Eric Fehrnstrom, a senior adviser. "I think it's going to be decided by the question voters are going to ask themselves, which is, 'Do I want another four years like the last four years?' And on that basis, I think Mitt Romney's going to win."

The Washington Post and Associated Press contributed to this report.