Brown admits Tory victory on the cards

Mr Cameron was picked as the winner of the third and final televised debate of the General Election campaign in a clutch of instant polls taken within minutes of the completion of the 90-minute BBC broadcast.

But a survey of more than 2,000 viewers' voting intentions put Conservatives neck and neck with Nick Clegg's Liberal Democrats on 36%, with Labour trailing on 24% just a week ahead of the May 6 election.

The three leaders locked horns on the economy and immigration in the debate, staged at the University of Birmingham just a day after Mr Brown was forced to apologise for branding pensioner Gillian Duffy "bigoted" when she raised concerns over migrants.

Mr Brown tried to draw a line under the row, issuing a plea to voters to judge him on his economic competence and not his personality.

"There is a lot to this job and, as you saw yesterday, I don't get all of it right," he said. "But I do know how to run the economy, in good times and in bad."

Mr Cameron said that a Labour victory next Thursday would mean "more of the same", while Liberal Democrats would bring "uncertainty.

Only an outright Tory victory could deliver "a clean break, taking our country in the right direction and bringing the change we need".

And Mr Clegg urged voters not to be frightened by the other parties out of voting for "real change".

"This is your election, this is your country," the Liberal Democrat leader said. "When you go to vote next week, choose the future you really want."

In his starkest admission yet that he may be leading Labour to defeat after 13 years in power, Mr Brown said: "I know that if things stay as they are, perhaps in eight days' time David Cameron, perhaps supported by Nick Clegg, would be in office."

But he said that both of the opposition parties represented "too big a risk to the economy".

And he said: "I don't like having to do this, but I have got to tell you that things are too important to be left to risky policies under these two people. They are not ready for government, because they have not thought through their policies."

A snap poll by YouGov for The Sun found that 41% of 1,151 viewers questioned thought Mr Cameron had won the debate, against 32% for Mr Clegg and 25% for Mr Brown.

Meanwhile, Mr Cameron was well ahead in a Guardian/ICM poll of 510 viewers on 35%, against Mr Brown on 29% and Mr Clegg on 27%.

But a ComRes survey of 2,372 viewers found the contest closer, with Cameron just two points ahead of Clegg on 35% to the Lib Dem leader's 33%, with 26% for Mr Brown.

At a rally shortly after the close of the debate, a shirt-sleeved Mr Cameron told jubilant supporters: "Don't waste one minute, don't waste one hour... We are going all the way."