If voters had gone to the ballot box this week, a new poll reveals Brown would have lost his majority to the Conservatives.

Poll reveals Labour ‘would have lost majority’

Poll reveals Labour ‘would have lost majority’

Labour have fallen five points behind the Conservatives, further validating Gordon Brown’s decision not to hold an autumn election.

Had Mr Brown decided to go to the polls tomorrow, he would likely have lost his overall majority while the Conservatives could have picked up as many as 70 seats, according to the latest opinion poll.

An ICM poll for the Guardian found support for Labour has dropped three points over the past month to 35 per cent, giving them their poorest rating since Tony Blair left office.

The prime minister might find some reassurance that support is still broadly comparable with the 2005 election result and six points above the low poll ratings seen by Mr Blair a year ago.

Support for the Conservatives has increased two per cent, placing them on the crucial 40 per cent barrier.

Translated into votes, this would have seen Labour lose their majority but remain the largest single party.

The ICM poll is the latest of seven opinion polls to put support for the Tories at or above 40 per cent and shows the strength of the party since their autumn conference.

Nevertheless, David Cameron’s aggressive stance against Mr Brown has not appealed to all voters, with 17 per cent saying they think less of him after the past month’s events.

Around one in five say their opinion of the Tory leader has improved, with 58 per cent unmoved.

Mr Brown has also fared badly, with 29 per cent saying they think less of the prime minister. Just eight per cent have been impressed by his performance.

His refusal to consider an EU referendum has angered many voters, with 53 per cent saying he was wrong to rule out a referendum, including 39 per cent of his own supporters.

The Liberal Democrats’ approval rating had slumped since Menzies Campbell’s departure. Support for the third party has, however, risen two per cent in the ICM poll, placing them on 18 per cent.

Labour hope the selection of a new leader will invigorate the Lib Dems and squeeze support for the Conservatives, bringing them back below the 40 per cent mark.

Support for all other small parties has meanwhile fallen to seven per cent, with no-one expressing support for the UK Independence Party, despite the strength of the Europe debate in recent weeks.