On August 8, 2000, six years ago to this day, Al Gore selected Joe Lieberman as his vice presidential running mate. After the 2000 election, Lieberman led in early polls for the ’04 presidential nomination. “Joe’s biggest problem is that he doesn’t have any enemies,” a Lieberman friend told The New Yorker in 2002.

Oh, those were the days. Tonight Lieberman learned that he had 144,336 voting enemies in the state of Connecticut, losing by four points, 52 to 48 percent, to insurgent challenger Ned Lamont.

Three months ago Lamont trailed by 45 points. A week ago he led by 13 points. Conventional wisdom said the race was narrowing. It did narrow, but conventional wisdom, in this race, was often wrong.

“They call Connecticut the land of steady habits,” Lamont said in the first line of his jubilant victory speech. “Tonight we voted for a big change.”

As results trickled in, the mood at Lamont headquarters in Meriden moved steadily from anxious to triumphant. For many of Lamont’s supporters, this was their first victory in a long time–or ever. As the Reverend Jesse Jackson Sr. told Lamont earlier in the day at a campaign event in Hartford, “your campaign represents hope.”

The hope that Democrats will hold their least progressive accountable. The hope that Iraq should be a central issue, not just a single issue, facing the country. The hope that a candidate few had heard of just months ago could knock off an 18-year Senator who’d become increasingly out of touch with his constituents.

“Stay the course–that’s not a winning strategy in Iraq,” Lamont said in his victory address, “And it’s not a winning strategy for America.” The crowd responded by loudly chanting, “Bring them home!”

During Lieberman’s faux-concession speech, a room full of dozens of bloggers affiliated with the Lamont campaign booed, laughed and clinked wine glasses. In a sign of how politics is changing, the room reserved for bloggers outnumbered the room designated for traditional media by a margin of 5-1.

“It’s a new Democratic Party we’re talking about,” Matt Stoller, a blogger for Mydd.com who helped recruit Lamont, told me. “Entirely new.”

It’s not often that a rich millionaire executive from Greenwich, Connecticut, leads a political insurgency. But Lamont has thus far been the right man at the right time. He ran a crisp, energetic, issue-driven campaign, based on strong opposition to the war in Iraq, support for universal health care and a desire to clean up Congress.

“We’re doing very well because we’re standing up and being bold about where we stand,” Lamont said earlier on election day.

In the end, voters rewarded clarity over compromise. And Lamont’s backers, many of them still young and idealistic, experienced the sweet smell of success. One day they will take over the Democratic Party. If so, consider tonight a beginning to that end.