The biggest winner is Howard Dean, left for dead after his infamous 2004 Iowa "scream." Lamont is a straight Deaniac, not just in his opposition to the war, but in his demographic profile: white, well-off and highly educated. These are the same people who backed the successful peacenik insurrection of George McGovern in 1972, and now they are bidding to make their control of their party all the more complete. Democratic commentator Marshall Wittmann calls the left-wing bloggers "McGovernites with modems."
Their main issue is the war, but they also represent a general repudiation of the one hiccup in the post-1972 McGovernite dominance of the party, the Clinton administration circa 1994-1998. Clinton was pro-growth, pro-free trade, tonally moderate and willing to use force abroad. Al Gore spurned this winning centrist formula in 2000, but he felt compelled to make a bow to it by picking the moderate Lieberman as his running mate. Now, the Democratic party is on the verge of saying a Lieberman-style hawkish-centrism is utterly anathema.
Lieberman could still win the primary. Even if he loses, he could win the general election as an independent, showing that the party's left wing doesn't have wider appeal. But if Lieberman is ousted from his seat, it will be a decisive victory for the party's haters and anti-war bloggers. The Democrats' muddle on Iraq will finally have ended, and the party will be the poorer for it.