WASHINGTON - Joe Lieberman, an outspoken maverick who represented Connecticut for 24 years, bid farewell to the Senate on Wednesday on a day he described as "filled with many emotions."

Lieberman addressed the Senate for the last time with half a dozen colleagues, characteristically from both sides of the aisle, in attendance. Among the senators were John McCain (R., Ariz.) and Lindsey Graham (R., S.C.), who with Lieberman are often referred to as the "three amigos." He spoke slowly but passionately for nearly 17 minutes as his staffers lined the edge of the chamber. Former staffers, friends, and family, including his wife, Hadassah, looked down from the visitors' galleries above.

Lieberman defied the Democratic Party in 2006 after he lost its nomination in a primary by running, and winning, as a third-party candidate. But he said that being chosen to run for vice president by Al Gore in 2000 "will forever remain one of my deepest honors." He was the first Jewish American nominated by a major political party for national office.

"And incidentally, thanks to the American people, I'm grateful to have received a half million more votes than my opponent on the other side, but that's a longer story," he joked, referring to the fact that he and Gore won the popular vote but lost the election.

Lieberman said his hope for the future of the Senate was the dismantling of the bipartisan gridlock, a step that "will unleash all the potential" of America.

All of his most important achievements, he said, were attainable only because both parties came together for the greater good.

"It's the partisan polarization of our politics which prevents us from making the compromises on which progress in a democracy depends."

It was nearly 50 years ago that Lieberman first set foot in the Senate chamber in Washington, as an intern to Connecticut Sen. Abe Ribicoff in the summer of 1963.

Earlier in the day, Majority Leader Harry Reid paid tribute to Lieberman on the Senate floor, calling the departing senator a "natural-born leader."

Despite their disagreements, Reid said, he never doubted Lieberman's principles and patriotism.

Lieberman led the successful effort to rid the military of the "Don't Ask, Don't Tell" policy, but also made a name for himself as a national champion for environmentalists, helping to negotiate the Clean Air Act of 1990 and leading efforts to protect the Arctic National Wildlife Refuge in Alaska from oil and gas drilling.

Toward the end of his remarks, Lieberman offered some foreign-policy advice to the 12 incoming senators.

"Do not listen to the political consultants or others who tell you that you shouldn't spend time on foreign affairs or national security," he said. "They're wrong. The American people need us, the Senate, to stay engaged economically, diplomatically, and militarily in an ever-smaller world."