Nick Clegg victorious in historic TV debate

The leader of Britain's third party took advantage of a rare chance to share equal footing with his opponents, and successfully lumped Labour and the Conservatives together, saying they had played "pass the parcel for 65 years" with UK voters.

In a snap poll taken just after the debate finished, Mr Clegg was shown to have won a crushing victory among viewers. Forty-three per cent said he had won the debate, with Conservative leader David Cameron second with 26 per cent. Prime Minister Gordon Brown was declared the weakest performer, with only 20 per cent of viewers saying he was the best debater.

Mr Clegg's victory in the debate will increase the likelihood of a hung parliament if his performance is reflected in improved poll ratings for the Liberal Democrats.

In an occasionally fiery hour-and-a-half debate, Mr Brown made a clear attempt to take the fight to Mr Cameron, accusing him of ducking questions on his spending cuts and taunting him over his "airbrushed" image.

Mr Brown also sought to "hug" Mr Clegg close, as Labour deployed their pre-prepared tactic of isolating the Conservatives.

Mr Cameron, meanwhile, gave a muted performance, and ended the debate by accusing Mr Brown of making "repeated attempts" to try to "frighten" voters about a Conservative government.

But it was Mr Clegg who was most successful in engaging the viewers, as he made a deliberate bid to capitalise on the anti-politics mood in the country at large.

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He also sought to distance himself from Mr Brown and Mr Cameron as they engaged in fierce exchanges with one another.

Their spat continued after the debate finished last night as, no sooner had the three men left the stage, a hectic "spin war" began behind the scenes in Manchester.

Labour accused Mr Cameron of a gaffe by mentioning China in the same sentence as Iran, as he sought to illustrate the external threats which showed why Britain needed to keep its nuclear deterrent.

But despite Labour's efforts, the results of the polls appeared to show that Mr Brown's gamble of being the first prime minister to accept the challenge of a live TV debate had backfired.

A Sun/YouGov poll released at the same time showed Mr Clegg's victory was even more marked, with 51 per cent of respondents believing he enjoyed the best of the exchanges. Mr Cameron was second on 29 per cent, with Mr Brown last on 19 per cent.

• Leaders debate: Body language analysis

Mr Clegg seized the initiative at the beginning of the programme as he was given the chance to speak first. He set the tone straight away, describing Mr Cameron and Mr Brown as "these two". "I'm here to persuade you that there is an alternative," he declared.

At the end of the debate, speaking directly to viewers at home, he declared: "I know that you think all politicians are the same. I hope I've shown you that isn't the case. They've played pass the parcel for 65 years, making the same promises and breaking the same promises."

The Lib Dem leader deployed the same tactic repeatedly. As Mr Brown and Mr Cameron sparred over the economy, Mr Clegg interjected: "The more they attack each other, the more they look exactly the same."

On party funding, he pointed to Mr Brown. He said: "You want to protect your union paymasters." He then turned to Mr Cameron: "And you want to protect the likes of Lord Ashcroft in Belize."

Mr Clegg was also helped by the fact that only Mr Cameron sought to take on Lib Dem policies. Mr Brown instead focused all his attacks on the Tories, and repeatedly sought to show he was in agreement with many Liberal policies.

• Leaders debate in quotes

Mr Brown quickly emerged as the most aggressive performer, taking Mr Cameron to task on his plans to cut spending in this financial year.

He was also the only candidate to issue a pre-prepared quip, mocking a Conservative poster which showed him grinning, but which the Prime Minister said was flattering to him. "I'm very grateful to you and Lord Ashcroft for funding that," he said to Mr Cameron. Then, in the most barbed moment of the opening exchanges, Mr Brown referred to another Tory poster from earlier this year which carried a huge picture of the Tory leader.

"You can't airbrush your policies, even if you airbrush your posters," he added. Mr Cameron hit back: "He has given this country the biggest budget deficit of any country in the world."

Mr Cameron was the only leader to tackle last year's expenses scandal head-on. He declared: "I am extremely sorry for everything that happened."

He was also the only one of the three who appeared to offer a concession on party funding. Under pressure over his party's funding by the Tory peer Lord Ashcroft, he said: "Yes, we've been too reliant for too long on rich individuals."

Mr Cameron then used his closing comments to slam Mr Brown's aggressive tactics. He said: "I think one of the things I've heard is just repeated attempts to try and frighten you over a Conservative government. And I said choose hope over fear."

However, Labour appeared unconcerned over Mr Clegg's victory as they continued to focus their attacks on Mr Cameron.

Home Secretary Alan Johnson said: "I thought Cameron would be better at the style. I thought Clegg did better on style."

But shadow chancellor George Osborne said: "You had Gordon Brown attacking, attacking, attacking. I didn't think that was very prime ministerial."

Scottish Liberal Democrat campaign manager Alistair Carmichael said: "Nobody else offers the programme for change and fairness that the Liberal Democrats do in this election."

However, SNP leader and First Minister in Scotland Alex Salmond stepped up his criticism of a debate from which he was excluded.

He said: "It was billed as a historic event, but what we got was three Westminster politicians looking the same, sounding the same and saying nothing of relevance to Scotland."

He added: "All the debate confirmed was that the London parties plan deep cuts to Scotland's budget and public services.

Over half the debate should have been captioned, 'Except for viewers in Scotland'."

In the same ComRes poll, Mr Cameron and Mr Clegg were rated neck and neck as the men most trusted to make cuts to public services. Thirty-six per cent backed the pair, with only 28 per cent supporting Mr Brown.

The Conservatives were found to be the most popular on immigration, however, winning 37 per cent of support. The Lib Dems were close behind on 35 per cent, with Labour third on 20 per cent.

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