SIX years ago Joe Lieberman was just a few Floridian hanging chads away from becoming US Vice-President. On Tuesday he faces ignominious defeat at the hands of a political novice in Connecticut.

A new poll suggests that the three-term Democratic Senator is trailing his anti-Iraq war challenger by 13 per cent, a 28- point swing since June, in the most closely watched primary election of the year.

Senator Lieberman is widely admired within Washington as a serious figure who has maintained his support for the Iraq war. The prospect of him losing to Ned Lamont is causing deep concern within the Democratic establishment, which fears that it would signal a shift in the party towards the strident anti-war Left which represents the majority of grassroot activists.

There is already talk of how this could affect the next presidential contest. Some evoke memories of Richard Nixon’s victory in 1968, which was helped by anti-Vietnam war campaigners refusing to rally behind Hubert Humphrey, the Democrats’ nominee regarded as complicit in the conflict.

Even Hillary Clinton, the likely frontrunner to be the Democrats’ choice in 2008, has belatedly begun tilting towards the prevailing anti-war sentiment in the party — although she still refuses to renounce her support for the invasion of Iraq.

Yesterday Senator Lieberman said that he hoped the poll would “shake up” his supporters to vote in the primary on Tuesday. But he has damaged his standing among Democrats by promising to run as an independent candidate if he loses the party’s nomination.

Although polls suggest that he is still popular among Connecticut voters, there is growing speculation that a crushing defeat would spell the end of his 36-year political career with senior Democrats likely to lean on him to pull out of the race.

Douglas Schwartz, the polling director for Quinnipiac University, which conducted the survey, said that a big loss for Senator Lieberman could alter voter perceptions. He said that the Senator’s campaign appeared to be “stuck in reverse” and Mr Lamont may now have the momentum for victory.

Senator Lieberman has shed some of his “genial Joe” image in the contest, attacking his opponent’s blue-chip background and largely-inherited multimillion-dollar fortune, which includes stakes in such firms as Halliburton and Wal-Mart.

But Mr Lamont told The Times: “People don’t give a hoot — they say at least you cannot be bought, you’re going to be your own man.” The Greenwich-based businessman’s family fortune is estimated at between $90 and $300 million. But he believes that most of the Democrats voting on Tuesday will be more motivated by hostility towards Senator Lieberman.

He conceded that he would not be standing if Senator Lieberman had not been so vocal in his support for the war. Mr Lamont voices the frustration of many Democrat activists when he asks why, when the overwhelming majority of Americans are disenchanted with the Iraq war, the likes of Senator Lieberman have failed to stand up to the President.

But Senator Daniel Inouye of Hawaii, one of a number of congressional colleagues who have campaigned for Senator Lieberman in the past week — despite his own opposition to the war — said that a Lamont victory threatened to make the Democrats “a one-issue party”.

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