A new poll has given the Conservatives a five point lead over Labour, which falls to its lowest level of support since the departure of Tony Blair.
The ICM survey for Wednesday's Guardian newspaper put the Conservatives on 40 per cent, up two since the last poll - carried out shortly before Gordon Brown announced he was not holding an autumn election.
Labour are on 35 per cent, down three points since the last survey, while the Liberal Democrats are up two on 18 per cent.
The decision not to call an election - expected to have been held on November 8 - has apparently harmed the prime minister's standing, with 29 per cent of respondents saying their opinion of him has fallen in the last month.
Only eight per cent said it had improved, a net decline of 21 points.
Had Brown proceeded with an autumn election, the poll suggested he would have been short of the 326 seats needed for an overall majority.
And the survey suggests the Tories are also squeezing the smaller parties, as it records no support for the United Kingdom Independence Party.
