The Conservatives have opened up an eight-point poll lead after increasing support among key voters.
A ComRes poll for the Independent places the Tories on 41 per cent after a seven point rise in the past month.
Support for Labour has fallen four points to 33 per cent, with commentators blaming Gordon Brown's handling of the election speculation.
Translated into votes at a general election, this would see Labour lose power with a two seat majority for the Conservatives.
Crucially for David Cameron, he has increased his appeal among men, young voters and those in the south-east, putting the Conservatives in sight of they key electoral battlefields lost in 1997.
Conservative support among men has risen from 31 per cent to 41 per cent since Mr Cameron's successful conference and bullish stance during the election furore. Support among women has also increased from 37 per cent to 41 per cent.
Labour's support among men has, by contrast, fallen from 40 per cent to 31 per cent, blamed on Mr Brown's apparent indecision over the election.
Mr Cameron has also begun to attract support from young voters, as well as depriving Labour of their lead in the south-east. The Tories can now claim 35 per cent support among 18 to 24-year-olds, while Labour have slumped 26 points to 15 per cent
As well as increasing support among metropolitan voters, the Conservatives are also mobilising support among their core voters.
Of those identifying as Conservatives, 93 per cent say they will back the party at the next election, compared to 81 per cent of Labour sympathisers.
Just 69 per cent of Liberal Democrats plan to back the third party, with 14 per cent planning to vote Tory and 12 per cent Labour.
Labour reportedly hope a new Liberal Democrat leader will increase the Lib Dem's appeal at the expense of Tory support.
Today's poll gives the Liberal Democrats their best rating, placing them up one point on 16 per cent. Other parties are down four on ten per cent.