Florida senator Mr Bob Graham has pulled out of the race for the Democratic nomination to contest the US presidency next year.
Trailing his Democrat rivals in both fundraising and opinion polls, Mr Graham announced the "difficult decision to withdraw" on CNN's Larry King Livetelevision programme.
A three-term senator and former chairman of the Senate Intelligence Committee, Mr Graham trailed in the polls and struggled to raise enough money to stay viable in a field of 10 Democratic candidates.
He said the late start to campaign, his role as chairman of the Senate Intelligence Committee, the congressional investigation of the September 11th attacks, heart surgery and war in Iraq were factors that weighed on his bid to win the Democratic nomination.
He did not immediately endorse any of the nine remaining candidates.