Lautenberg said he would devote himself over the next two years to passage of tougher gun laws, which he has long advocated.
He said a primary challenge was "not at all" part of his decision. But as he walked off the Senate floor after an afternoon vote, he said he was "disconsolate" about leaving a job he loved - and sorely missed when he briefly retired in 2000.
"I liked serving here," he said, mentioning also his Army service and his memories of receiving a Columbia University degree presented by Dwight D. Eisenhower, then the school's president. But he said it was time to open the door to others. New Jersey has not had a Senate primary without an incumbent since Lautenberg's first retirement, which lasted just two years.
"I will have been here 30 years when I finish," he said. "There's got to be room for follow-on from the state of New Jersey, and with 30 years of service, I think that the time was right."
He added, "It was nothing other than clear decision-making."
As he spoke, Sen. Charles E. Schumer (D., N.Y.) walked by. "Chuck-O!" Lautenberg called.
Schumer clapped him on the shoulders and said, "He's the greatest. We're going to miss him."
Lautenberg's landmark legislation includes banning smoking on airplanes and setting a national blood-alcohol definition of 0.08 for drunken driving. He has long taken pride in punching at the National Rifle Association and pushing for tougher gun laws, even when the issue was considered a political nonstarter.
"Frank is a steadfast champion of the people of New Jersey," President Obama said in a statement.
Political insiders had expected that Lautenberg would step aside, but his decision threw open the wrangling to replace him. Booker, 43, has created a committee to raise money for a Senate run, and Democratic Rep. Frank Pallone said Thursday, "I'm interested in the Senate seat and I'm certainly going to continue to explore it, but today is about Sen. Lautenberg."
The top two Democrats in the state Legislature, Senate President Stephen Sweeney of Gloucester County and Assembly Speaker Sheila Oliver of Essex County, have also said they are considering running.
One Democratic source suggested that even more star power could be added if Patrick Kennedy, son of the late Democratic Sen. Edward M. Kennedy, jumps in.
Kennedy, a former Rhode Island congressman and recent Jersey Shore transplant, has been seen at high-profile New Jersey political events, but on Thursday he said, "I don't see myself as a candidate in 2014." He said he is most focused on helping New Jersey host the Special Olympics national games that year.
Among Republicans, State Senate Minority Leader Thomas H. Kean Jr. of Union County, who ran for the U.S. Senate in 2006, is seen as a potential contender. So is Assembly Majority Leader Jon Bramnick of Union County.
Booker, with a national profile, a fervent Twitter following, and a penchant for headline-grabbing heroics, is seen as the heavy favorite in a Democratic primary. A Monmouth University/Asbury Park Press poll released Thursday morning showed him winning 40 percent of the vote in a hypothetical primary, compared with 25 percent for Lautenberg, 4 percent for Pallone, and 2 percent for Sweeney.
Pallone, though, has $3.4 million in campaign funds and has been quietly working on winning over party warlords.
"Pallone is doing all the things necessary to launch a campaign," Kennedy said. "If he ends up running, I can really see being very enthusiastic about campaigning for him."
Booker has his critics. He angered Democratic insiders who had hoped he would run against Gov. Christie and thought his talk of a Senate run was disrespectful to Lautenberg.
And while Booker issued a statement Thursday praising Lautenberg as a "champion of the people of New Jersey," the senator didn't warm up to the Newark mayor.
"Every day I go to work, I go to Newark; every day I go to work, he leaves," Lautenberg said, prodding the perception that Booker is more focused on his national profile than his city. Asked if they had spoken, Lautenberg said: "He doesn't have my number."
The comments were typical for the senator, who has walked with a cane since a recent illness and rarely mustered the effort to stand during Obama's State of the Union speech Tuesday, but who remains as sharp-elbowed as ever.
Christie, a Republican, said he and the Democratic senator "have had our differences ... but I've always respected him for his tenacity, devotion to the people of New Jersey, and his love for and commitment to public service."
The son of Russian and Polish immigrants, Lautenberg grew up in Paterson and will return there Friday to formally announce his plans.
Lautenberg, who with two friends founded the payroll processing giant Automatic Data Processing, leaped into politics in 1982 at age 58, running for a Senate seat and winning his first elected office.
He retired in 2000 and soon regretted it. A chance to return came when Sen. Robert Torricelli chose not to seek reelection in 2002. Democrats put Lautenberg on the ballot instead.
New Jersey politicians looking to advance, though, have often eyed his seat.
Rep. Robert E. Andrews ran in a primary against Lautenberg in 2008, but was soundly beaten. Andrews said it was "extremely unlikely" that he would run for Senate again, though he added, "You never say never."
Flu and bronchitis forced Lautenberg into an extended absence from the Senate late last year. He missed several votes, including some on aid for victims of Hurricane Sandy.
Lautenberg said he hoped to spend more time with his wife, Bonnie, and 10 grandchildren.
"I leave here feeling good about the contributions that I've been able to make," he said, but added that he was also focused on one last big fight: another push for new gun laws.
With the topic now part of the national discussion, Lautenberg said, "I've got work that I really want to finish."
The Life of Lautenberg
Some key dates in the life and political career of Sen. Frank Lautenberg (D., N.J.), who announced
he would not seek reelection in 2014.
Jan. 23, 1924: Born in Paterson, N.J.
1952: With two friends, launches Automatic Data Processing, a payroll company that becomes one
of the world's largest.
1982: Enters politics, winning an open U.S. Senate seat in a race against Millicent Fenwick.
1984: Writes a bill, later signed into law by President Ronald Reagan, to withhold federal highway funds from states that do not set 21 as a minimum age to buy and possess alcohol.
1988: Wins reelection over Pete Dawkins.
1989: Is the prime sponsor of a 1989 law that
bans smoking on all domestic flights of less than
1994: Wins reelection over Chuck Haytaian.
2000: Does not seek reelection and retires from
the Senate at the end of his term.
September 2002: Enters the Senate race after Sen. Robert Torricelli bows out. Defeats Republican Doug Forrester two months later.
2008: Wins reelection over Dick Zimmer after surviving a primary challenge from Rep. Robert E. Andrews.
February 2010: Days after the death of Sen. Robert Byrd makes Lautenberg the oldest member of the Senate, he is diagnosed with lymphoma of the stomach. He undergoes chemotherapy and is declared in June to be free of cancer.
January 2012: In interviews, Lautenberg says he's "entitled" to seek reelection, while Newark Mayor Cory Booker publicly says he is interested in running for the seat in 2014.
Feb. 14, 2013: Announces he will not seek reelection in 2014.
SOURCE: Associated Press
Contact Jonathan Tamari
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