"I've faced much tougher obstacles in my life," Martinez said.
"My decision is not based on re-election prospects, but on what on what I want to do with the next eight years of my life."
Martinez, 62, was elected in 2004 after serving as the U.S.
secretary for Housing and Urban Development during the Bush administration. He served as general chairman of the Republican National Committee for 10 months, resigning in October 2007.
Martinez was born in Cuba. At the age of 15, he fled to America as part of a Catholic humanitarian effort called Operation Pedro Pan. Catholic charitable groups provided Martinez, who was alone and spoke virtually no English, a temporary home at two youth facilities. He then lived with two foster families, with whom he remains close. He was reunited with his family in Orlando in 1966.
In appointing Martinez in 2001, Bush said he was "the embodiment of the American Dream." Martinez said during his announcement that he wants to continue to encourage the hopes and dreams of other Hispanics.
"I always tried very much to be a mentor and role model, particularly to young people," Martinez said.
Martinez played a big role in getting Congress to pass a bill attempting to save Terri Schiavo, the brain-damaged woman at the center of a bitter right-to-die battle.
He also worked to protect oil drilling off Florida's coast, helped secure the release of a Florida woman being held prisoner in Vietnam for political activism and added language to a health care bill the Senate passed that would double Medicare fraud penalties.
Speculation about who would run for Martinez' seat began immediately after his announcement.
A spokesman for Democratic U.S. Rep. Kendrick Meek of Miami said the congressman was "definitely looking into it." Outgoing Florida House Democratic leader Dan Gelber, who was elected to the state Senate last month, said he was considering a run, and a spokeswoman for Republican U.S. Rep. Vern Buchanan of Sarasota said the congressman was receiving calls of encouragement.
Other names mentioned as possible candidates include Democratic U.S. Rep. Ron Klein of Palm Beach County and former House speakers Marco Rubio and Allan Bense, both Republicans.
