By Bart Jansen, Rachel Kapochunas and Jonathan Allen, CQ Staff

Senate Republican Whip Trent Lott , who considered retirement before the 2006 election but instead returned for a fourth Senate term, said Monday he will resign by the end of this year.

“It’s time for us to do something else,” Lott, 66, said at a news conference in Pascagoula, Miss., with his wife, Patricia. He said he does not have plans “lined up” after he leaves the Senate but suggested that teaching may be one option he will explore.

Lott said his health was not a factor in his decision and that tougher lobbying laws affecting former members did not play a “big role” in his decision. .

He said he would remain through the current session of Congress, to help wrap up unfinished business. “I want to continue to serve in my position as whip right to the end of the session,” he said.

Lott’s announcement prompted an outpouring of tributes from colleagues in both chambers. Minority Leader Mitch McConnell , R-Ky., said, “Trent is the best whip I’ve ever worked with, and I’m pretty familiar with the requirements of the job.” McConnell was GOP whip in the last Congress.

House Minority Whip Roy Blunt , R-Mo., also praised Lott’s prowess as whip — a leadership position that entails prodding, coaxing, cajoling and, above all, vote-counting.

“As the person often credited with building the modern whip organization in the House, Trent’s many contributions to this chamber are difficult to fully appraise – but impossible to ignore,” Blunt said in a statement. “Indeed, his 16 years here [1973-89] were enormously important to this chamber – and enormously influential on how the House would come to be run once he left for the Senate.”

Leadership Scramble

Lott’s departure will trigger the second shake-up of the Senate Republican leadership team in slightly more than a year.

Senators looking to move up are scrambling to gauge their support for the various posts.

The early speculation was that Republican Conference Chairman Jon Kyl of Arizona, currently No. 3 on the leadership ladder, would be elected whip and the rest of the leadership team would each move up a step.

Lamar Alexander , who lost to Lott by a single vote in the secret-ballot election for GOP leaders in November 2006, threw his support to Kyl for whip. But Alexander said he would compete for the post that Kyl would vacate — making him one of as many as five GOP senators interested in becoming conference chairman.

“If Jon is elected, I will be a candidate to succeed him as chairman of the Republican Conference,” Alexander said in a written statement. “That is where I believe I can make the greatest contribution to the effectiveness of the Senate and our Republican Conference.”

A source close to Sen. Kay Bailey Hutchison , R-Texas, who currently chairs the GOP Policy Committee, said she, too, will run for the No. 3 post.

Another potential contender is Sen. Jim DeMint , R-S.C., according to a Republican aide. DeMint is promoting his business background in marketing and his current leadership of the Republican Steering Committee.

DeMint, who campaigns to limit government spending and cut taxes, might also seek Lott’s seat on the Finance Committee, according to the aide.

Sen. Richard M. Burr , R-N.C., was poised to jump into the conference chairmanship race if it comes open, a source close to the lawmaker said, as was Sen. John Thune , R-S.D. But neither formally entered the race.

“He’s considering conference chair or policy [committee chair],” said a source close to Thune. “He’s talking to folks, gauging interest. No decisions have been made.”

If Hutchison competes for conference chairman, Cornyn will run for chairman of the Policy Committee, a Cornyn aide said.

Second Act

Two years ago, Lott was ready to retire. He changed his mind largely out of a sense of duty, saying he wanted to help his state recover from Hurricane Katrina. He also was worried about family finances, having lost a home to the hurricane. And he still had something to prove inside the Senate.

Lott had been ousted as Senate Republican leader after the 2002 midterm elections, his colleagues moving quickly and decisively to isolate him amid a torrent of negative publicity following Lott’s remark at Sen. Strom Thurmond’s 100th birthday party that America would be better off if Thurmond’s 1948 presidential bid had succeeded. Thurmond, R-S.C. (1954-56, 1956-2003) had run as a segregationist.

Lott was succeeded as Senate Republican leader by Bill Frist of Tennessee (1995-2007.)

In his 2005 memoir, “Herding Cats: A Life in Politics,” Lott criticized Frist, saying Frist’s run for majority leader in late 2002 was a “power grab” and a “personal betrayal.”

Special Elections

When Lott resigns, Republican Gov. Haley Barbour must appoint a replacement within 10 days to serve until a special election is held in November 2008 to fill the remainder of Lott’s term. Barbour, who was just re-elected, is as much of a Beltway insider as it’s possible for a sitting governor to be, having been Republican National Committee chairman and a Washington lobbyist.

Mississippi’s other senator, Republican Thad Cochran , is running for re-election in 2008, meaning both Senate seats will be up at the same time. And one of the state’s House seats will be up, as well.

Speculation on who Barbour might put in the Senate focused on Republican Rep. Charles W. “Chip” Pickering Jr. of the 3rd District. Pickering, 44, has long held aspirations for higher office. He announced his own retirement from the House in August, at a time when it seemed neither Senate seat would be up in 2008. Pickering was forced to defer his Senate ambitions in 2006, when Lott was rumored to be considering retirement but decided to seek another term.

Republican Rep. Roger Wicker also has been mentioned as a possible successor.

Former Attorney General Mike Moore is the most prominent Democrat mentioned as a possible candidate for the seat in 2008.

The Senate seat is very likely to remain in Republican hands. Like many states in the south, Mississippi has trended strongly Republican in recent years after decades of Democratic control. The last Democrat to hold a Senate seat in Mississippi was John Stennis, who was re-elected to his final term in 1982.

Sen. John Ensign of Nevada, chairman of the National Republican Senatorial Committee, released a statement expressing confidence the GOP will hold Lott’s seat.

“We are confident that voters in Mississippi will continue Senator Lott’s legacy, and we will work closely with Gov. Barbour and state officials to provide any necessary support,” Ensign said.