Republican presidential hopeful Sen. John McCain, R-Ariz., right, gives a thumbs-up after Florida Gov. Charlie Crist endorsed him for president Saturday at the Pinnelas County Lincoln Day Dinner in St. Petersburg, Fla.

St. Petersburg, Fla. ? Florida Gov. Charlie Crist endorsed a beaming Sen. John McCain on Saturday night, delivering a boost three days before the state’s pivotal primary.

Crist praised McCain as a “true American hero.” At a county GOP dinner in St. Petersburg, Crist added, “After thinking about it as much as I have, I don’t think anybody would do better than the man who stands next to me, Sen. John McCain.”

It was the second high-profile endorsement in as many days for McCain, who is locked in a tight primary race with former Massachusetts Gov. Mitt Romney. Crist stepped to the podium a little more than 24 hours after Sen. Mel Martinez announced he was backing his colleague in the Senate. Officials said Martinez, who campaigned Saturday with McCain, had prodded the governor to follow his lead.

Crist said he would campaign for McCain in the coming days. “I just feel in my heart he’s the right man for the job at the right time,” he told reporters afterward.

The winner of next week’s primary will capture all 57 delegates at stake, a large prize that will set the stage for a virtual nationwide primary on Feb. 5.

Crist’s endorsement was sought by all the GOP presidential rivals, including Romney, former New York Mayor Rudy Giuliani and former Arkansas Gov. Mike Huckabee.

McCain said the nod “means a lot in this race.”

“I’m honored and privileged,” McCain told reporters. “And I intend to work very closely with him on the issues. We’ve got to provide home insurance for every person who lives in the path of a hurricane. We are going to have to work together to save the Everglades and other great environmental treasures of this state.”

He quipped: “We will continue to compete for both baseball spring training and for tourism.”

McCain does not support a national catastrophic insurance fund for Florida and other hurricane-prone states, instead saying he could bring industry and government together to protect homeowners. Crist does support a national fund.