LIBERAL Democrat leader Nick Clegg was declared the clear winner of Britain's first TV election debate, after the party leaders traded blows on schools, hospitals, crime and the economic crisis.

After an historic night in Manchester, two separate polls suggested Mr Clegg had triumphed over both Gordon Brown and David Cameron, the Conservative leader, after 90 minutes of cut-and-thrust.

One survey, carried out for ITV News, found that 43 per cent of 4,032 voters rated the Lib Dem leader the winner, against 26 per cent for Mr Cameron and 20 per cent for Mr Brown.

A second poll declared a similar result, with 51 per cent of the 1,091 people questioned by YouGov picking Mr Clegg, comfortably ahead of the Tory leader (29 per cent) and the prime minister (19 per cent).

The much-hyped debate passed without any of the three would-be prime ministers committing the sort of gaffe that might have destroyed their party's chances in the election on May 6.

It also, surprisingly, lacked the expected witty one-liners that have lit up some of the presidential debates in the United States - only Mr Brown raising a small laugh from the 200-strong audience.

Instead, the debate was heavy on policy detail, frequently featuring Mr Brown attempting to isolate the Conservative leader, saying repeatedly: "I agree with Nick."

Both the Labour and Tory leaders performed competently - and did nothing to undermine support among their traditional supporters - but, arguably, did nothing to change the course of the campaign.

Mr Clegg arguably gained the most simply because he was by far the least well-known of the leaders before the debate started, given the media's frequent ignoring of the Lib Dems outside of election campaigns.

The early skirmishes featured Mr Clegg condemning "greedy bankers", Mr Brown warning of a "double-dip recession" under the Tories and Mr Cameron condemning the expenses scandal.

On immigration, the Conservative leader attacked an increase of two million migrants over the last decade, but found both other leaders attacking his plan for a strict cap on incomers.

Mr Clegg delivered the most eye-catching attack, warning that the hard-line Conservative plan might, if the limit had been reached, prevent a top footballer coming "to play for Manchester United".

On crime, Mr Cameron talked vividly about a woman he met in Merseyside who was burgled by an ex-prisoner who set fire to her sofa and killed someone - yet could be free in just four-and-a-half years.

Mr Clegg hit back by condemning prisons as "overcrowded colleges of crime", while Mr Brown - not for the last time - attacked the Tories for planning to cut Labour's spending, this time on police.

The prime minister fired off perhaps the only successful joke of the entire 90 minutes, thanking Mr Cameron for putting up thousands of poster featuring him smiling. "I'm very grateful to you and Lord Ashcroft......"

But he also took the big risk of appearing too aggressive, interrupting the Conservative leader and challenging him directly, saying: "Be honest with the public - because you can't airbrush your politics, even if you can airbrush your posters".

On expenses, Mr Cameron described how the scandal had been "horrendous" and left him "angry", while also accepting the Conservatives had been "too reliant on rich individuals", such as Lord Ashcroft.

The Lib Dem leader appeared to score a hit by arguing passionately for smaller class sizes, while Mr Cameron struck a traditional Tory stance, saying: "Change the rules, so teachers can keep order in class,"

The education debate featured Mr Brown returning to his favourite theme that Conservative plans to cut 6bn from spending in this year - to reverse Labour's planned national insurance (NI) hike - would bring disaster.

He said: "It can only end up with the loss of thousands of jobs, including teachers". But Mr Cameron accused the prime minister of "a figure plucked out of the air", adding: "This is a complete invention."

Still on the budget deficit, Mr Cameron called the NI rise a "jobs killer, a recovery killer, an economy killer", but Mr Brown warned: "I fear for what might happen. We do not want a double-dip recession in this country."

Mr Clegg, meanwhile, condemned "mythical savings" promised by both parties, insisting the budget deficit couldn't be cut by "getting rid of paper clips and pot plants in Whitehall".

Attacking Mr Cameron directly for pretending he could cut the deficit, increase spending and offer a "blizzard of tax breaks", adding: "You might be able to do one of those things - you can't do all three."