Tallahassee ? Republican Sen. Mel Martinez’s decision Friday to step down 16 months early gave Gov. Charlie Crist the perfect gift: his pick of who should watch over the office while Crist tries to win it for himself.

Crist responded carefully, immediately passing on the opportunity to install himself as the incumbent leading up to the GOP primary. He is likely to pick a placeholder Republican who will not run against him, meaning Martinez’s resignation will have no immediate effect on the balance of power in the Senate, where Democrats control the 60 seats needed to overcome Republican filibusters.

Martinez, 62, had already announced he wouldn’t seek re-election, but his early departure immediately sharpened the focus on a race that the GOP can ill afford to lose next fall.

The only Hispanic Republican in the Senate, Martinez said he was making good on a promise to voters that he wouldn’t simply keep the seat warm.

“There’s no impending reason, it’s just my desire to move on,” he said.

Martinez, known as a voice on immigration and issues involving Cuba, crossed party lines Thursday to vote in favor of Judge Sonia Sotomayor’s nomination to become the first Hispanic on the U.S. Supreme Court.

He said Friday that the next phase of his life will be in the private sector, but he didn’t have any specific plans. He said he would serve until his replacement was named; Crist promised to try to make his selection before the Senate returns from its summer break after Labor Day.

Much of the talk about whom Crist would nominate centered on former Florida Secretary of State Jim Smith, 69, who told The Associated Press on Friday that he would love to have the job for a little while.

“I’d go tomorrow,” Smith said from Colorado Springs where he and his wife, Carole, were vacationing. “It would be a great way to end a public career.”

Crist bypassed a likely safe re-election bid by getting into the Senate race where he is being challenged by former state House Speaker Marco Rubio, a West Miami Republican. Rubio is banking on support from GOP conservatives unhappy with the governor for his support of President Barack Obama’s economic stimulus plan and because of his lukewarm opposition to abortion and gay marriage.

U.S. Rep. Kendrick Meek of Miami is the only major Democratic candidate.

Florida’s senior U.S. senator, Democrat Bill Nelson, is midway through his second term.

Crist, who has earned a reputation for having a strong political antenna, will want to make his pick appear as one that won’t look like it’s clearing the path for his election next year.

“The best way to make it easy for him would be to do the right thing and that is pick a well qualified person to do the job,” said former state GOP party boss Van Poole. “And I think that’s what he’s going to do.”

University of Virginia political scientist Larry Sabato said the appointment is an opportunity for the Florida governor — one way or another.

“This is a great opportunity, but you can blow an opportunity,” Sabato said. “The worst thing he could do was to appoint a flunky or himself.”