Washington (CNN) -- For at least three undecided voters, both candidates left an impression during Wednesday's debate.
Mitt Romney, they said, came to play. Barack Obama, they said, let them down.
Until late on October 3, Micheal Fazio, 41, of Las Vegas, leaned toward the president. But Obama's "disinterested" performance in the debate in Denver left him concerned.
Fazio said Obama wasn't on point.
"As the president of the United States, I hate to say it, no rest for the weary," said Fazio, who voted for Obama in 2008. "If he's not sharp in the debate ... what's he going to be like behind closed doors?"
Chuck Taylor, 66, a North Carolina retiree, said Romney impressed him.
"I was impressed, as many people were with Mr. Romney's debating skills," Taylor said. "I thought the president for whatever reason was not on his game."
But polls show Fazio and Taylor aren't alone in their assessment of the candidates' performances.
According to a CNN/ORC International survey taken just after the debate, 67% of registered voters who watched the debate said that the Romney won the contest. One in four said Obama won the 90-minute event.
"No presidential candidate has topped 60% in that question since it was first asked in 1984," says CNN Polling Director Keating Holland.
With the candidates neck-and-neck in national polls ahead of the debate, any edge is valuable, especially with undecided voters who make up somewhere between 3% and 8% of the electorate.
"They're important because with voters on both sides seemingly unwilling to switch teams," David Di Martino, a Democratic strategist and partner at Blue Engine Media, said, "these last undecided voters -- let's call them the "6%", will put either candidate over the top whenever they decide to break one way or the other."
A battleground poll of likely North Carolina voters taken ahead of the debate shows Obama leading Romney by two points with six percent undecided in the state. A similar poll in battleground state, Nevada shows Obama leading Romney by two points with three percent of likely voters undecided.
Polling for undecided voters post-debate is not available.
But will the candidates' performances make a difference in the election?
Fazio says it kept his vote up for grabs.
"I've been undecided for the longest time," Fazio said. "For the past month to six weeks I've been leaning toward Obama."
Fazio said he was looking for Obama to nail down his vote during the debate. Obama, Fazio said, didn't deliver.
Another undecided voter, Jason Mencher, 26, a Hofstra University law student, voted for Obama in 2008. The New York resident said ahead of the debate that he was completely neutral, but the candidates' face off pushed him toward Romney.
"I'm not happy with what Obama did in the past four years," Mencher said. "I think Romney is a viable alternative, but I don't know what he would do specifically."
But he said nothing in the debate would have changed his mind "besides some extreme event like a major meltdown" by either candidate.
In the history of televised presidential debates, only two have shifted the tide of an election -- 1960 and 2000, according to a Gallup Politics analysis. Those elections, Gallup explains, were close -- like the election this year.
Wednesday's debate impacted voters but it isn't likely to alter the tide.
The debate "kept both of them squarely tied, so it didn't sway the campaign either way," said Christine Riordan, dean of the Daniels College of Business at the University of Denver, site of the debate.
Instead, voters say they are looking toward the next three debates -- two presidential and one vice presidential -- to make a decision and to clear up their concerns.
Fazio says that he is worried Romney will revert to the policies of George W. Bush.
"It scares me to stick the Republicans back in there." Fazio said.
He also added that at this point in the election, he's watching out for mistakes -- because consistency matters.
"I hate saying this ... but I am waiting for a gaffe from one of them to say, 'Oh my goodness, this is the straw that broke the camel's back.'"
Taylor is looking for someone who can corral Congress.
"I think that the president, while it's an important position, is not the problem here. It's the Congress that's the problem," Taylor said. "And you've got to have a leader who is going to be able to abandon their extreme ideas and come together on a compromise on those positions, for instance, the national debt."
Mencher wants fewer anecdotal stories, negative political sparring, and more logic and facts.
"The person who is going to lead the free world is making low blows on stage?" Mencher asked. "That would lose my vote."
And what comes up in the next round of debates could be significant.
"The second and the third debate become more critical in the minds of the undecided voters," Riordan said.
Those debates could bring up some of the more "volatile" issues that weren't talked about Wednesday night, she said.
"There weren't any social issues introduced," which affect important voting blocs of women and Hispanics in swing states like Colorado, Riordan said.
Undecided voters who tend to vote wait until the last minute to cast their ballots, said Jan Leighley, professor of government at American University.
"If you don't have to buy a new cell phone for another month, you probably won't buy it today," Leighley said.
But for Fazio, because of the debate, he says he couldn't vote today.
"If you had me pencil in a vote today, I couldn't tell you who I was going to vote for."