Clegg’s debate win gives Lib Dems huge poll boost

Lord Mandelson will be regretting telling hacks in the Manchester 'spin room' last night that Nick Clegg had clearly won the great TV debate. He can have had no idea at the time just how well Clegg had done.

A sensational ComRes poll of 4,000 people who watched the ITV programme puts the Liberal Democrats on 35 per cent, only one point behind the Tories on 36 per cent, as the result of Clegg's success. The same poll has Labour third on 24 per cent, totally eclipsed by Clegg's Liberal Democrats.

It revives memories of the soaring support once enjoyed by the SDP - and is likely to be just as short-lived, especially after ComRes issued a rider later this morning, explaining that if their poll is extrapolated across the adult population as a whole, then voting intentions are: Tories 35 per cent, Labour 28 per cent and Lib Dems on 24 per cent.

That's not quite as exciting as their first press release – but it's still a massive morale boost for the Lib Dems and possibly a game-changer in this election if Clegg can exploit his obvious success in front of the TV cameras.

The fact is, it was hard to tell who was running faster in ever-decreasing circles this morning: the spin-doctors trying to understand the significance of Clegg's win in the debate, or the pollsters trying to extrapolate from an instant survey of 4,000 viewers what the results might mean nationwide.

Lord Mandelson, who is in charge of Gordon Brown's election strategy, was pumping up Clegg last night in the belief that the Lib Dems couldn't harm Labour, but might take away seats from the Tories, particularly in the south of England and the West Country.

But the ComRes poll suggests the real threat to Labour now is that, with the wind behind them, the Lib Dems could overtake Labour in their heartlands. Former Labour fortresses like Sheffield have already been stormed by the Lib Dems and it could happen elsewhere in the north if disgruntled Labour voters look for another party on May 6.

Mandelson may argue that the poll is a rogue, and just a blip. But 4,000 voters is a big sample and, even if it only applies to those who actually saw the show, a 14 points rise in support overnight for the Lib Dems (from 21 per cent to 35 per cent) is a big deal.

Furthermore, a smaller ICM poll for the Guardian showed a quarter of viewers were now ready to change their vote as a result of the debate - and the majority of those (54 per cent) said they would switch to the Lib Dems.

The audience for the historic debate – the first ever in a British general election – was 9.9 million, lower than some had hoped for, but much, much higher than cynics had foreseen, the Mole included.

And what the viewers saw, and how they reacted, has had a profound effect. This general election just got very interesting. ·