(CNN) - Sen. Mel Martinez, R-Florida, announced Tuesday will not seek reelection in 2010.
In a Florida press conference, Martinez said his decision was not based on the likelihood he would face a tough reelection fight.
"I've faced much tougher obstacles in my life," he 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."
The first term senator and onetime National Republican Committee chairman narrowly won his first Senate race in 2004. Martinez also served as Secretary of Housing and Urban Development during President Bush's term.
One congressional source cited Martinez's age, 62, and said "he is ready for the next chapter in his life."
It currently appears 19 GOP seats will be up for grabs in 2010.
(CNN) - Senate Democrats appear willing to let Sen. Joe Lieberman keep his powerful Homeland Security Committee chairmanship, even though the Connecticut independent campaigned vigorously for John McCain's White House bid, two congressional sources told CNN Monday.
Instead, Senate Democrats will likely strip Lieberman of his chairmanship of an environmental subcommittee - a considerably less prominent position than his homeland security post.
That outcome would be at odds with Senate Majority Leader Harry Reid's initial intentions. Sources told CNN last week that Reid had informed Lieberman it was likely he would lose his chairmanship of the committee and instead assume a leadership post on a less prominent panel. Lieberman told
Reid that offer was "not acceptable," according to sources.
The Democratic caucus will formally meet Tuesday morning to hold a secret ballot vote on Lieberman's future, but the sources suggested the outcome of that vote may already be a foregone conclusion.