Voters are increasingly writing off Labour as fewer people believe that a change of leader or policy would help the party to win the next general election.

A Populus poll for The Times, undertaken over the weekend after Labour’s defeat in Glasgow East, suggests that its dramatic slide in popularity is being driven by a collapse in economic confidence.

Labour is on 27 per cent, down one point on the last Populus poll three weeks ago, and about the level it has been for the past three months. This is the lowest since the early 1980s.

The Conservatives are on 43 per cent — up two points — with the Liberal Democrats down one point at 18 per cent. Other parties are unchanged on 12 per cent.

Ministers plotting to remove Gordon Brown receive a warning that barely half the electorate (52 per cent) believe that it would improve the party’s fortunes. This is roughly the same as when the question was asked last in May, despite increased speculation about his future. There has been a three-point rise, to 44 per cent, in the number saying that even replacing him with “a younger, fresher, more charismatic alternative” would not make Labour more likely to win.

There is little other comfort for the Prime Minister or for increasingly worried Labour MPs: the number of voters who believe that significant policy changes in areas such as the health service, crime and tax would make a difference has fallen from 69 to 56 per cent since May. The number saying that new policies would not boost Labour has jumped from 26 to 41 per cent.

There has been a small increase to 40 per cent in the number believing that a big Cabinet reshuffle bringing in more fresh faces would help Labour, but this is counterbalanced by the 55 per cent saying it would not assist.

The poll shows how economic pessimism has taken hold. While in April a narrow majority (50 to 47 per cent) believed that they and their families would be better off in the coming year, today 66 per cent fear they will be worse off. Just 32 per cent remain optimistic. Last September there was a net plus of 27 points in those believing they would be better off, as opposed to worse off.

Similarly, the number thinking that Britain as a whole will do well economically has fallen from 39 to 22 per cent since April. It was more than 50 per cent a year ago. More than three quarters (77 per cent) think that the country will do badly, up from 59 per cent in April and 45 per cent last September.

Moreover, pessimism is highest among those who voted Labour in 2005 but have since switched to the Conservatives — at 86 per cent for the country as a whole, and 66 per cent for them and their families.

Senior ministers, including Harriet Harman, the deputy leader, continued to tour television studios yesterday to insist that Mr Brown was the best man to lead the party. Efforts to stamp out the rebellion were undermined, however, when another MP called for him to quit. Gordon Prentice, Labour MP for Pendle, said that a leadership election would help to restore a Government that had become a “bit rusty.”

“A Prime Minister needs a different set of skills from a Chancellor of the Exchequer,” he said. “A Prime Minister must be able to communicate, persuade and enthuse. If not, the message is lost. I hope Gordon reflects on things during August and accepts that it is in the party’s best interests, and perhaps his own, for him to stand down.”

A junior member of the Government heaped further pressure on Mr Brown by calling on him to announce windfall taxes on energy companies and banks in the run-up to Labour’s conference in September.

Rob Marris, a parliamentary aide to Shaun Woodward, the Cabinet minister, said: “I don’t think the policies are clear enough yet and I don’t think we are getting the messages through.”

Populus interviewed a random sample of 1,002 adults aged over 18 by telephone between July 25 and 27. Interviews were conducted across Britain and the results have been weighted to be representative of all adults. More details: www.populus.co.uk.

For more details, see www.populus.co.uk

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