The Conservative lead over Labour has dipped into single figures after months in which David Cameron enjoyed a double-digit advantage, according to a new poll.
The ICM poll for The Guardian put the Tories on 40% (down two points on a similar survey last month) Labour on 31% (up two) and the Liberal Democrats on 18% (down one).
It is the first ICM survey since December 2008 to put the Tory lead at less than 10 points, and the third major poll this month to report a single-figure margin between the two main parties' support.
Labour's vote share in The Guardian's regular poll has now increased for the fourth month in a row, from a 25% low in August.
Although the figures would almost certainly deliver Mr Cameron a majority in the Commons if replicated in a general election, Labour supporters may be encouraged to think that the mood of voters is shifting in their direction.
They will increase pressure on Prime Minister Gordon Brown from within the party to consider an early election on March 25, rather than the May 6 date considered most likely by many pundits.
Some 19% of those voters questioned said that Chancellor Alistair Darling's Pre-Budget Report last week would make the economy worse overall, against 12% who thought it would make things better.
Meanwhile, 31% said that Mr Brown and Mr Darling were best placed to manage the economy, against 38% for Mr Cameron and shadow chancellor George Osborne.
ICM Research interviewed 1,009 adults by telephone between December 11 and 13.
