Stakes Big For GOP Senate Hopefuls TAMPA (WUSF) - Anyone who thinks the stakes aren't big for who becomes the Republican nominee for Senate hasn't heard this commercial:

PRESIDENT BUSH: I'm honored to be with a great American. Mel Martinez, who makes a big difference in our cabinet.

Mel Martinez has shown little reluctance to use the most powerful politician in the land to promote his candidacy. Almost every picture on brochures touting Martinez are scenes with President Bush.

That's no big surprise, given that Martinez was secretary of the federal Department of Housing and Urban Development. And that Martinez has been hand-picked by the national Republican leadership to take on front-runner Bill McCollum, who lost four years ago to current Senator Bill Nelson.

The latest polls show McCollum's lead slipping and is now at 29 percent. Support for Martinez has risen to 25 percent. Far back in the pack are Florida House Speaker Johnnie Byrd and political newcomer Doug Gallagher.

During a campaign swing this week in Clearwater, Martinez promised more ads are on the way.

MARTINEZ: I think that gap is probably non-existent by now, I'm willing to predict. I think we're moving forward into a commanding position in the race, and we'll be closing strong with TV. We've had a lot of TV advertising in this area already, and you're going to see Mel Martinez on the air between now and August 31st.

A recent poll shows that 30 percent of likely Republican primary voters haven't made up their mind on who to support. McCollum is betting that a lot of those voters have national security on their minds.

COMMERCIAL: Long before 9/11, a lone voice warned Bill Clinton about Osama bin Laden. Congressman Bill McCollum. The Bill McCollum story. A story about of honor, patriotism, integrity and conservative values....

During a debate that aired Tuesday night locally on WFLA television, the former Congressman from Orlando trumpeted his experience on security.

McCOLLUM: I founded the House Task Force on Terrorism and chaired it, I served on the House Intelligence Committee. I'm the one candidate who doesn't need on-the-job training to go to the United States Senate and represent the people of Florida on a host of issues, but especially on terrorism and national security.

The Republican race has generally focused on who could show the most conservative credentials.

During the debate, the four major candidates marched in unison on issues such as education, abortion and preserving President Bush's tax cuts. They differed only slightly on issues such as the use of fetal stem cells for medical research.

But McCollum was faulted for losing his first Senate campaign. Byrd was criticized for his leadership of the Florida House, and Gallagher for his political inexperience. And Martinez was attacked by the others for not supporting a lower cap on jury awards for medical malpractice cases. Gallagher got to ask him a question.

GALLAGHER: As a personal injury lawyer, you got to make a living by suing the likes of Disney and Sea World, and even the First Baptist Church of Orlando in slip-and-fall cases. Yes or no, Mel. Will you join Mickey Mouse, Shamu, me and even the Lord himself by finally endorsing a two-hundred-fifty-thousand cap on medical malpractice? MARTINEZ: Gosh Doug, I liked it better when they were asking the questions.

Byrd has said he has the most conservative credentials of them all. He wants to keep the president's tax cuts permanent, and exercise fiscal restraint in Washington.

BYRD: We stopped taxing and spending here in Florida. We're living within our means. That's a problem in Washington. We need to make sure that they go up and don't continue what I call borrowing and spending. We can't afford it.

Gallagher, whose brother Tom is the state's chief financial officer, says he's a businessman - not a career politician.

GALLAGHER: I've created hundreds of jobs in the private sector. I understand what the fundamentals are. And also, I would cap federal spending, the increase in it, at no more than the rate of economic growth. If the economy doesn't grow, then we don't increase federal spending.

Only candidates receiving at least five percent support in the polls were invited to take part in the debate. The other candidates on the ballot are Miami lawyer Larry Klayman, former fighter pilot Sonya March of St. Petersburg, and businessman Billy Kogut © Copyright 2013, WUSF