Clegg survives attacks over 'illegal migrants amnesty' - VIDEO

The Liberal Democrat leader came out top in at least one of the polls released immediately after the debate, although other instant reaction gave David Cameron top billing after a disappointing first debate for the Tory leader.

Mr Clegg admitted his policy – which would allow law-abiding illegal immigrants who have been in the UK for more than 10 years to "earn" the right to stay, branded an "amnesty" by critics – was "controversial" as Mr Cameron and Gordon Brown warned it would encourage more migrants to try to reach Britain.

But Mr Clegg, who was also told by the Prime Minister to "get real" and withdraw his opposition to a "like-for-like" replacement of the nuclear deterrent and told by Mr Cameron to get off his "pedestal" over MPs' expenses, said there needed to be an honest debate.

The Sheffield Hallam candidate still came out top in a poll by ComRes for ITV News, with 33 per cent of viewers saying he won and the other two men tied on 30 per cent. But Tory leader Mr Cameron topped another poll by YouGov for The Sun with 36 per cent, against 32 per cent for Mr Clegg and 29 per cent for Mr Brown.

Mr Cameron brought the debate to life when he accused Labour of spreading "lies" the Tories would scrap pensioner benefits such as the winter fuel allowance, and demanded Mr Brown withdrew the leaflets.

The leaders also clashed over the possibility of a hung parliament, Afghanistan, Europe and the economy.

In passionate concluding remarks at the end of the 90-minute debate, Mr Clegg pleaded with voters not to listen to those who were "spreading fear" and claimed "something really exciting is beginning" after causing a sensation by topping some opinion polls this week. Presenting himself as an alternative to the "old parties," he said: "There is still some way to go before this election is decided, but I hope that you agree with me that something really exciting is beginning to happen.

"People are beginning to believe and to hope that we can do something different."

Mr Cameron accused the Prime Minister of sounding "slightly desperate", saying the country needed to make a "clean break from the last 13 years".

He argued the Conservatives were best placed to offer change, "rather than being stuck with what we have now".

Mr Brown told viewers "the buck stops here" and claimed he was best placed to lead the country through the economic recovery, branding his opponents a risk to the economy and UK security.

In his opening address he said the debate may "have the feel of a TV popularity contest" but said the election was about Britain's future.

"If it is all about style and PR, count me out," he said. "If it is about the big decisions, if it is about judgment, if it is about delivering a better future for this country – I am your man."

Last night's debate – the second of three during the election campaign – dealt with international affairs for the first 45 minutes before moving on to the general issues.

After last week's comprehensive win for Mr Clegg, which has sent support for the Lib Dems soaring over the past seven days, Mr Cameron needed to regain some ground amid signs of a Tory wobble with two weeks to election day.

He appeared to have learned from some of the Lib Dem leader's tactics, staring into the camera to address viewers directly for much of the debate.

Shadow Chancellor George Osborne and Shadow Defence Secretary Liam Fox immediately declared the evening a success for Mr Cameron, but Labour Ministers were claiming a victory of substance for Mr Brown.

Donation claims dismissed as 'nonsense'

Nick Clegg dismissed as "complete rubbish" questions over donations that went into his personal bank account.

The Liberal Democrats moved to draw a line under the story last night by releasing details of his financial arrangements as Mr Clegg described the issue as a "complete nonsense story" during the TV debate.

Allegations in the Daily Telegraph formed part of a barrage of hostile headlines that threatened to undermine a successful week for Mr Clegg following last week's first debate.

Figures released by the party show donations from three private donors amounting to 19,690 were paid into Mr Clegg's account between January 2006 and January 2008. But according to the Lib Dems' figures Mr Clegg paid 20,437.30 into party coffers between March 2006 and February 2008 for staffing costs.

Copies of Mr Clegg's personal bank statements submitted during 2006 to back up his expenses claims recorded "automated payments" from Ian Wright, a senior executive at drinks firm Diageo; Neil Sherlock, the head of public affairs at accountants KPMG; and Michael Young, a

former gold-mining executive.

All three men confirmed they had paid the money to help fund a member of staff for Mr Clegg's office.