JACKSONVILLE, Fla. -

With just four weeks to go until the general election, the presidential campaigns are making a final push to expand the electorate in their favor.

As the last day to register to vote in Florida came Tuesday, both campaigns were making a last minute effort to gain support.

Since last week's debate, a growing number of polls are putting Mitt Romney ahead of President Barack Obama. Before the debate, the conventional wisdom was that Obama was up, but Romney's performance has clearly given him some momentum with voters.

Experts warn polls are a good indicator of trends, but zeroing in on the percentages isn't the most accurate.

Seldom since John F. Kennedy trounced Richard Nixon, or Ronald Reagan said he was paying for the microphone has a debate had so much impact on a presidential race.

"When the president of the United States again gets -- not just doesn't get beat, but really gets obliterated in substance and style in front of 60 million people, it's forcing people to look at Mitt Romney," said Lenny Curry, chairman for the Republican Party of Florida.

The boasting has been at a fever pitch from the GOP, with the polls flipping in Romney's favor. Democrats, however, aren't as quick to say Obama will be a one-term president.

"I think you'll see Obama come on strong in the next debate," said Billee Bussard, director of communications for the Duval County Democratic Party. "Certainly, I think Joe Biden is going to do a good job. You've got to remember the president is also the president and trying to do that job as well as campaign."

According to a Pew Research Center survey, 49 percent of likely voters say they back Romney, and 45 percent support Obama. The survey was done four days after the debate in Denver.

Gallup's poll of likely voters over the last week show Romney with a 2-point advantage over Obama, 49 percent to 47 percent.

"If you look at the polls in general from a broader perspective and you look at a number of polls day after day, they can give you the general direction of what's going on," said Matthew Corrigan, a political science professor at the University of North Florida. "They're useful, they help drive fundraising, they get people excited when the poll results are good, they can deflate campaigns when poll results are bad."

Experts say people need to be wise consumers of polls, which are likely to come out every day from now until Election Day.

They say people should look at the methodology, who's sponsoring the poll and when the surveying was done.