Updated

New Jersey Democrats announced Tuesday night that they had chosen former Sen. Frank Lautenberg to replace Sen. Robert Torricelli on the November ballot.

The decision was reached after a full day of meetings among senior state party officials, and announced by Gov. James E. McGreevey at a press conference.

The Democrats have a one-seat majority in the Senate, and Torricelli, tainted by allegations of corruption, was suffering from a double-digit lag behind his Republican challenger. 

Lautenberg became the Democrats' choice after they considered his legislative record and his stand on social issues, which matched the party line, McGreevey said.

Lautenberg told reporters he was ready to run and then serve in the Senate.

"None of the enthusiasm has died," Lautenberg said. "I will fight just as hard. I am just as energized."

Earlier in the day, Lautenberg said he had misgivings about campaigning, but would put them aside.

"I was there [in the Senate] 18 years, and I enjoyed virtually every day," Lautenberg said in a telephone interview from his car as he headed to the governor's mansion for meetings with top state Democrats. "I didn't like raising the money, but I'm not going to mind it as much this time, because it's kind of a fresh start."

Rep. Frank Pallone had been tapped by state Democratic leaders to take the job, but Pallone, who has sought statewide office before, said no because his wife wouldn't let him run, Democratic sources said.

Democratic operatives told Fox News they chose Pallone over Lautenberg because of age. Lautenberg is 78 years old and Pallone will turn 51 on Oct. 30. They predicted Lautenberg would still beat the Republican candidate, businessman Doug Forrester.

Forrester's campaign quickly denounced Lautenberg.

"When it comes to Mr. Lautenberg, the voters are going to say, 'Been there, done that.' It's time for new leadership," said Forrester's campaign manager, Bill Pascoe.

During the marathon negotiations, several men were offered the job, party sources familiar with talks said.

Robert Menendez, the fourth-ranking Democrat in House leadership, took himself out of the running by saying he wanted to focus on winning a Democratic House majority.

Assemblyman Joseph J. Roberts of Camden was also a choice, but national party leaders were concerned he did not have enough name recognition to win a statewide race. Discussions focused on Pallone by late afternoon Tuesday, but he then withdrew.

Whether Lautenberg's name will appear on the ballot with Forrester will be decided by the state Supreme Court. Republicans say it is too late to replace Torricelli, who dropped out Monday as his poll numbers continued to fall amid questions about his ethics.

The New Jersey Supreme Court will hear arguments on the case Wednesday.

Sen. William Frist, chairman of the Senate GOP campaign committee, said Republicans would consider an appeal to the U.S. Supreme Court if the New Jersey court rules in favor of the Democrats.

"This is a desperate grasp at getting around the law and the people of New Jersey are tired of having their leaders go around the law," he said.

Frist said some absentee ballots had already been cast and that other ballots had been distributed to military personnel overseas; the New Jersey Association of County Clerks said about 1,600 absentee ballots had been mailed out.

Senate Majority Leader Tom Daschle, D-S.D., said that by objecting to Torricelli's request, Republicans were "denying the people of New Jersey a choice" in the election.

Five months ago, Torricelli's Senate seat was considered relatively safe. But support plummeted after he was admonished by the Senate ethics committee for his financial relationship with a 1996 campaign supporter, and he soon became the most vulnerable incumbent in the country.

Few, however, expected a court fight five weeks before Election Day.

"This is one for the books," said Larry Sabato, a political scientist at the University of Virginia. "It will long be remembered."

Under New Jersey law, a party can replace a statewide nominee on the ballot if the person drops out at least 51 days before the election. Torricelli missed that deadline by 15 days.

However, Democrats say decades of state court decisions put voters' rights above filing deadlines and other technical guidelines.

Attorney General David Samson argued in papers filed with the court Tuesday that the justices have the power to relax the deadline to withdraw and allow Democrats to post another candidate. Samson, who was appointed to his job by McGreevey, said election laws have long been interpreted liberally to allow voters every opportunity.

Legal experts agreed.

"In a substantial number of those cases, the courts have ruled on the side of being inclusive," said Richard Perr, an election law professor at Rutgers University Law School.

Six of the seven justices on the state's highest court were appointed by a former Republican governor.

Lautenberg's selection as the potential Democratic savior is replete with irony. He and Torricelli feuded openly while serving together.

"I'm not in a gloating mode," Lautenberg said. "I don't want to be smug about this. It was unfortunate for him and an unfortunate thing for all of us."

Lautenberg is a supporter of abortion rights and staunch opponent of the death penalty. He brings two major strengths to the difficult bid: statewide name recognition and a huge reserve of personal wealth he can use in the campaign.

Unlike the House members who were also considered as substitute candidates, Lautenberg does not have anything to lose by running and losing.

Lautenberg was a business executive before serving three terms in the Senate, deciding against a re-election bid in 2000. He counted among his accomplishments a law requiring companies to disclose chemicals they release into the environment, a law banning smoking on domestic flights and a law banning gun ownership by those convicted of domestic violence.

The Associated Press contributed to this report.