Speaking in St. Louis, Gephardt said, "Today my pursuit of the presidency has reached its end. I am withdrawing as a candidate and returning to private life after a long time in the warm light of public service."
He has previously said the run for president would be his final run for political office. But he said that he would complete his present term in Congress, saying he has always worked for the hard-working Americans and that "effort is not going to cease in the coming months."
Gephardt ran as the champion of unionized workers, and won the endorsement of 21 unions during his run for the nomination.
Gephardt, 62, has represented Missouri's Third Congressional District since 1976. He served in party leadership positions since 1984 and was elected House majority leader in 1989. He kept the Democrats' top spot in the House until after the 2002 elections that saw the Republicans make substantial gains in the House.