Support for the Conservative Party is so flimsy that Labour could head off a general election defeat by ousting Gordon Brown, according to a survey for The London Independent.
ComRes found that Labour would do better under all eight alternative leaders, whose support it tested with the public, than under Mr Brown. Under David Miliband, the Foreign Secretary, or Jack Straw, the Justice Secretary, Labour would be the largest party in a hung parliament, raising hopes that it might cling on to power for a fourth term.
According to ComRes, the Tories would be the largest party in a hung parliament, but still deprived of an overall majority, if Labour were led by Ed Miliband, the Energy and Climate Change Secretary; Ed Balls, the Schools Secretary; Alan Johnson the Home Secretary; Harriet Harman, the Commons Leader and Lord Mandelson, the Business Secretary.
But David Cameron would win a majority of 24 under backbencher Jon Cruddas and 48 if Mr Brown leads Labour into the election.
The stark findings will sharpen Labour's debate over whether the Prime Minister should stand down for the sake of his party. His backbench critics are bound to cite the poll as evidence that a change of leader could transform Labour's prospects.
But yesterday the Cabinet and the party rallied strongly behind him as he declared his determination to fight on, saying: "I do not roll over". Brown allies said the survey showed that "Operation Fightback", launched as the Labour conference in Brighton got underway, could work because Tory support was so shallow.
Cabinet ministers dismissed suggestions that they would move against Mr Brown in December if he has not closed the poll gap by then. One told The Independent: "There is no Plan B. We are sticking with Gordon. As soon as you even think about Plan B, you dilute Plan A – to get back in the game under Gordon."
The relatively low ratings for Mr Johnson, seen as the only "unity candidate" behind whom the Cabinet would rally, will raise doubts about his leadership credentials. But allies of David Miliband will be pleased that he tops the poll of alternative leaders.
The ComRes survey makes grim reading for Labour. It is neck and neck with the Liberal Democrats on 23 per cent, with the Tories on 38 per cent and other parties on 16 per cent. The Lib Dems are up two points on last month, the Tories down two, while Labour is down one point and other parties up one.
The Tories have at least twice as much support as Labour among both ABs and C1s – the key group middle classes that Mr Brown is desperate to win back and has put at the heart of his fightback strategy. The Tories are also ahead of Labour among C2s and DEs and are ahead in every region of Britain except Scotland.
More than half (53 per cent) of people who voted Labour in 2005 but have now deserted the party say they would be more likely to support the party if someone other than Mr Brown was leading it, while 43 per cent would not. Overall, one in three (33 per cent) of people who intend to support other parties say they would be more likely to switch to Labour under a different leader, while 63 per cent would not.
Some 54 per cent of Labour supporters agree with the statement that Mr Brown would be remembered more positively as a Labour leader if he were to stand aside.
There was one ray of hope for Mr Brown in the findings. Some 49 per cent agree with his claim that the Government's actions have stopped Britain's recession turning into a longer term depression.
Voters appear to want public spending to be cut rather than taxes raised to help fill the black hole in the public finances. By a margin of 60 to 37 per cent, they oppose tax rises.
In an unscheduled extra appearance on the Labour conference platform, Mr Brown, who makes his keynote speech tomorrow, insisted that his personal prospects were not what mattered. "It is not about the future of me, our MPs, the Government. It is about the future of our country," he said. "This is a battle for what we believe in."
Earlier he had to fend off questions about whether he took prescription painkillers from the BBC's Andrew Marr, who raised rumours which have surfaced in right-wing political blogs. There was fury among Brown aides that the question was asked and there were protests to BBC bosses. Mr Brown replied with a simple "No."
Asked if he ever doubted whether he was the right man to lead Labour and the country, Mr Brown responded: "Of course, you say 'some people think someone else could do the job better'. I have got to consider that. But I don't have doubts, because I have started doing something very difficult."
ComRes telephoned 1,003 British adults between 25 and 27 September 2009. Data was weighted by past vote recall. ComRes is a member of the British Polling Council and abides by its rules.