Mitt Romney is fighting to earn a new look from voters with 30 days remaining until the election, as President Barack Obama looks to close the window on his Republican challenger. 

Romney, the Republican presidential nominee, has hopes of building momentum off of his strong debate performance this week, in which he generally outperformed Obama with energetic and crisp arguments.

But a top spokesman for the president vowed Sunday that Obama wouldn't allow Romney a repeat performance in their second showdown.

"It's not rocket science to believe the president was disappointed in the expectations he has for himself," former White House press secretary Robert Gibbs said on "Meet the Press" of Obama's debate performance, which was panned as lethargic and lacking in aggression.

Of the second debate, scheduled for Oct. 16, Gibbs said, "I think you're going to see a very engaged president that is ready and willing to call out whichever Mitt Romney shows up."

Romney "walked over" Obama in Denver, former House Speaker Newt Gingrich, one of Romney's erstwhile primary opponents, contended. But Gingrich also acknowledged that the GOP nominee had "changed" from the primary, when he vowed to cut taxes for individuals in all income brackets. (Romney said in Wednesday's debate that, in his reform plan, the wealthy wouldn't end up paying any less in taxes.)

Whether Romney has made up much ground versus Obama hasn't yet been fully reflected in polls conducted since the debate. The Republican hopeful entered the matchup trailing the president, and must make up ground — especially in battleground states like Ohio — if Romney is to have any hope of winning on Nov. 6.

"The real question to me, of this campaign, is, can the Romney campaign take this moment and run with it?" asked Mike Murphy, a longtime Republican consultant with ties to Romney.

Romney won the endorsement of a newspaper in one such swing state, Nevada, as the editors of the Las Vegas Review-Journal said Romney "has the principles and experience needed to put America back on the road to prosperity."

But Obama's case for re-election was bolstered Friday by a new jobs report that showed the unemployment rate at 7.8 percent in September, clearing the psychological barrier of 8 percent, above which the unemployment rate had sat for months. 

"I think it was a significant help to the president," Gingrich said of that report.

Obama's advantage over Romney was fueled partly by improving perceptions of the economy, which could be cemented by the new employment data. If nothing else, the president will have a new cudgel to wield against Romney in their next debate matchup. 

Both Romney and Obama will leave it to their running mates this week to carry the banner on Thursday, at the vice presidential debate. 

"I know Vice President Biden is anxious and ready to do this," Gibbs said of Biden's impending debate versus Wisconsin Rep. Paul Ryan, the Republican vice presidential nominee.

In the meanwhile, both the president and Romney aren't taking the weekend off; instead, they're both on the campaign trail this Sunday. Romney will hold a rally this afternoon in Florida, while Obama attends a "30 days to victory" fundraising concert tonight in Los Angeles.

DENVER – Policy largely trumped “zingers” in the first debate between President Barack Obama and Republican presidential nominee Mitt Romney as the two sparred on issues as varied as taxes and spending, entitlements, education and more.

Romney sought to cast himself as a capable and affable alternative to the sitting president and looked to establish himself as presidential in a major opportunity to reach voters in a side-by-side setting at the University of Denver. Hitting that mark was especially important for Republican presidential nominee, given the high expectations he had faced entering tonight’s forum, having trailed Obama in most polls before this event.

Michael Reynolds / AP

President Barack Obama shakes hands with Republican presidential nominee Mitt Romney after the first presidential debate at the University of Denver, Wednesday, Oct. 3, 2012, in Denver.

Obama, for his part, cast his Republican opponent as elusive in specifying just how he would cut taxes without adding to the national debt, or what form his own health care reforms would take. 

But neither candidate seemed to achieve any breakout moment, and two additional debates throughout October could prove more pivotal to the election’s outcome.

VOTE: Did the debate do anything to influence who you will support on Election Day?

Taxes and spending dominated the outset of the debate, as Obama and Romney battled largely over the details of Romney’s tax proposals, which call for an across-the-board, 20 percent reduction in each marginal tax rate. The Republican argues the cost of these would be offset by reducing deductions.

"My number one principle is there will be no tax cut that adds to the deficit," Romney said.

Romney asserted his tax plan would spur job creation and help balance the budget, but the president insisted that these proposals simply do not add up.

Slideshow: On the campaign trail

Reuters, Getty Images

In the final push in the 2012 presidential election, candidates Mitt Romney and Barack Obama make their last appeals to voters.

Launch slideshow

"The fact is that if you are lowering the rates the way you described, governor, then it is not possible to come up with enough deductions and loopholes that only affect high-income individuals to avoid either raising the deficit or burdening the middle class," Obama said. "It's math. It's arithmetic."

With a few exceptions, both candidates largely avoided the snappy, practiced lines that sometimes come to define debates. Their discussion at many times overrode the objections of moderator Jim Lehrer, and some of the topics for debate had to be shortened or cut altogether to accommodate for the candidates’ long-windedness.

PhotoBlog: Over beers, laundry and straight razor shaves, Americans tune in to the presidential debate

In a time-honored debate tradition, both campaigns’ surrogates declared victory for their candidate of choice. But style for both Obama and Romney seemed as important of a factor as any specific answer. 

Romney entered the debate needing to make up ground versus Obama, and the matchup this evening offered voters their first chance to make a direct comparison between the two of them. The Republican nominee also sought to soften his tone in many respects, a bow toward the net-negative personal approval rating he suffers in many polls.

Truth Squad: The Denver debate

Obama campaign manager Jim Messina told reporters following the debate that the president’s long-windedness was “never going to be our strong suit,” and acknowledged that Romney had scored “style points.”

“This is a race to 270 electoral votes,” Messina said. “In states like Ohio and Virginia and Florida, Romney’s positions on tax cuts and Medicare are going to be real problems for him. And he doubled down on those all night.”

But Obama didn’t score a knockout punch against Romney, declining to employ the controversial video about the “47 percent” of Americans whose votes the GOP nominee had essentially dismissed. Obama declined to talk about Romney’s record at Bain Capital or the personal income tax rate paid by Romney – two major, effective lines of attack used by the Democratic campaign over the summer.

Romney also parried many of the president’s attacks by largely embracing the essence of many of Obama’s own policies – from health care to education and regulation – while emphasizing the areas in which the two of them differed.

Romney said he supports repealing the Dodd-Frank financial regulatory reform law, but replacing it with an alternative of his own. He has said that about immigration, and defused a briar patch involving his and Obama’s similar health care plans by seizing upon process.

“I like the way we did it in Massachusetts. I like the fact that in my state, we had Republicans and Democrats come together and work together,” said Romney. “What you did instead was to push through a plan without a single Republican vote.”

Toward the end of the debate, Obama struck back by questioning whether Romney’s own promises were too good to be true.

“At some point, I think the American people have to ask themselves, is the reason that Gov. Romney is keeping all these plans to replace secret because they're too good?” Obama asked.

The immediate fallout of the debate will be most quickly reflected in media cycles on Thursday and into the weekend, though it might take days’ worth of polling to identify whether tonight’s debate moved the needle.

Obama and Romney will next meet Oct. 16 for the second of three debates. Before then, Vice President Joe Biden and Republican vice presidential nominee Paul Ryan will debate next Thursday in Kentucky.

TAMPA, Fla. – Arizona Sen. John McCain expressed concern Sunday that further weather-related cancellations of the Republican National Convention here could deprive the GOP of an opportunity to make its case to voters.

Speaking Sunday on “Meet the Press,” the 2008 Republican presidential nominee said that the decision by convention organizers to effectively cancel Monday’s session due to the effects of the impending Hurricane Isaac wouldn’t have much harm on Republicans.

Jacquelyn Martin / AP

Sen. John McCain, R-Ariz. attends a news conference about the Convention of the Rights of Persons with Disabilities, Thursday, July 12, 2012, on Capitol Hill.

“It's Wednesday, Thursday night that are the big moments,” he said. “It's not that we don't want that first night, but I don't think it will be harmful if we lose the first night.”

But, the veteran senator added: “It could be harmful if we lose more than that.”

Recommended: Hurricane impending, Republicans cancel first day of convention

Republicans announced on Saturday that they had decided to delay the beginning of the convention until Tuesday; the impending storm threatens logistics and safety problems that made it unfeasible to convene for Monday’s activities.

But convention organizers haven’t yet released the revised schedule, and haven’t officially foreclosed the possibility of further weather-related changes to the schedule bleeding into Tuesday.

Related: GOP elders describe high stakes for Romney in Tampa

As things stand, Ann Romney and New Jersey Gov. Chris Christie are scheduled to be featured speakers on Tuesday evening. Mitt Romney won’t speak until Thursday, though the formal roll call vote to nominate him for president is currently scheduled for Tuesday.