For most of the past week, John McCain was slightly behind Mitt Romney in Florida’s Republican Presidential Primary. Then, on Saturday, the Arizona Senator switched the subject of the campaign to his comfort zone--national security issues. Saturday night, the Arizona Senator got another bit of good news—an endorsement by popular Florida Governor Charlie Crist.

Polling on Sunday showed that McCain picked up four percentage points from the day before. Mitt Romney and Rudy Giuliani lost two points each and Mike Huckabee also slipped a point. As a result, it’s all tied heading into the final full day of campaigning before Florida’s Republican Presidential Primary.

The latest Rasmussen Reports telephone survey in Florida shows McCain and Romney tied at 31%, Giuliani is a distant third at 16% and Huckabee is in fourth place at 11%. The number of persuadable voters is also dwindling. Only 2% are undecided and just 6% say there’s a good chance they could change their mind.

Seventy-nine percent (79%) of McCain’s voters have already voted or are certain they will vote for him. That number is identical for Romney voters. Just 5% of McCain voters and 7% of Romney voters say there’s a good chance they could change their mind.

The election may be decided by the number of Giuliani and Huckabee supporters who decide to abandon their first choice in hopes of influencing the outcome. Many may have already done so. On Saturday, 15% of Giuliani supporters said there was a good chance they could change their mind. Just 7% of the remaining Giuliani voters said the same on Sunday.

Fifty-two percent (52%) of Florida’s Republican Primary Voters say that it’s more important to select a President who can handle national security issues than one who can handle economic issues. Thirty-five percent (35%) take the opposite view.

Voters have this preference for national security credentials despite the fact that 43% name the economy as the top voting issue. Just 28% name either the War in Iraq or national security as the top issue. One reason may be that Republican voters in Florida generally believe that the best thing the government can do to help the economy is to get out of the way. In terms of stimulating the economy, 47% say cutting government spending is the best policy. Thirty-nine percent (39%) say cutting taxes is most important.

It is hard to overstate the impact of Florida’s Republican Primary. While it is highly likely that both McCain and Romney will continue regardless of the outcome, a win for McCain would make him the heavy favorite for the nomination. He already leads or is tied for the lead in several Super Tuesday states including in California, New York, New Jersey, Missouri and Alabama.

On the other hand, a victory for Romney could give Romney a bounce for Super Tuesday and set the stage for a long, drawn-out competition.

Nationally, in the Rasmussen Reports daily Presidential Tracking Poll, McCain and Romney have begun to pull away from the rest of the field. The economy is seen as the top voting issue for all voters nationwide.

Rasmussen Markets data suggests that McCain has a % chance of winning in Florida while Romney is given a % chance.. According to the markets, Giuliani is a distant third with a % chance of victory. Numbers in this paragraph are from a prediction market, not a poll. Using a trading format where traders "buy and sell" candidates, issues, and news features, the Rasmussen Markets harness competitive passions to provide a reliable leading indicator of upcoming events. We invite you to participate in the Rasmussen Markets. It costs nothing to join and add your voice to the collective wisdom of the market. Prospects for California and other races are featured on the Rasmussen Markets Summary page.

Among Florida Democrats, Hillary Clinton has a substantial lead.