With his wife, Tricia, at his side during a news conference in Pascagoula, Miss., Lott said that after 35 years in the House and the Senate, "It's time for us to do something else."
The departure by year's end means that Lott, whose home was destroyed by Hurricane Katrina, could accept a position lobbying his former colleagues one year after he leaves office under the current law, instead of waiting for two years, as is required under the new Senate ethics law that goes into effect in January.
Lott has told the Biloxi Sun-Herald that the Pascagoula home was his "nest egg," and sued his insurer, State Farm Fire & Casualty Co., to pay for rebuilding.
Lott, 66, a former majority leader in the Senate, might be best remembered for remarks he made at Strom Thurmond's 100th birthday party, when he saluted the South Carolina senator with comments widely interpreted to be supportive of segregation. Lott later apologized for his "poor choice of words," which he said "conveyed to some the impression that I embraced the discarded policies of the past. Nothing could be further from the truth."
At the time, the White House publicly distanced itself from Lott, and the loss of support eroded his base, forcing him to step down as majority leader. Lott wrote a book, Herding Cats: A Life in Politics, in which he said that President Bush's cold shoulder was "devastating ... booming and nasty."
Lott called the president Sunday to tell him of his decision. In a White House statement, Bush said yesterday that Lott "has always been a leader - someone his colleagues have known they could count on to stay true to his principles." The president said Lott's "immense talent will be missed in our nation's capital."
Calling his years in Washington "a wild ride," Lott said yesterday that he is proud of his achievements and is leaving with "no malice, no anger" - though he has said in the past that being in the Senate minority is not as much fun as being in the majority when you "like to get things done."
Saying that he might like to teach, Lott speculated that perhaps he could manage his son Chet's musical career and noted that he had submitted his name to University of Mississippi Chancellor Robert Khayat for the position of head football coach at Ole Miss.
"I don't know what the future holds for us. A lot of options, hopefully, will be available. I've always thought I might like to teach some - as the son of a schoolteacher, why wouldn't I want to do that?
"'You may have played pretty good football on the corner of Lake Avenue and Morgan Lane in Pascagoula, but you ain't going to be a football coach,'" Lott said the chancellor told him. "So I guess that's not an option."
Lott's job in the Senate often required the former college cheerleader to cajole colleagues into voting the leadership's way. A Republican colleague, Sen. Charles E. Grassley of Iowa, was unstinting in his praise for Lott's roles as majority leader, minority leader and whip.
"It's hard for me to imagine the United States Congress, and especially the Senate, without Trent Lott being a part of it," Grassley said in a statement. "Senator Lott has been both a leader and a maverick. He knows the ins and outs and all the maneuvers of the legislative process. Nobody worked the whip process better. He's fought for legislation that respects the principles of less government and more freedom. He's fought hard, and won big, for his constituents. He brings tremendous energy and drive to his work, and I'll greatly miss Trent Lott as a colleague."
Mississippi Gov. Haley Barbour, a Republican, said he will appoint a replacement to serve for the next year and that there will be an election next November to fill the remaining four years of Lott's term.
Mississippi has not elected a Democrat to the Senate since 1982, when John C. Stennis defeated Barbour.
Johanna Neuman writes for the Los Angeles Times.