CHARLES KENNEDY’S election campaign sparked into life last night as hundreds of supporters had to be locked out of his first election mass meeting.

About 500 people crowded into the Guildhall at Cambridge, on the day that the former Labour MP Brian Sedgemore defected to the Liberal Democrats.

Hundreds more queued in the rain outside but were turned away. Mr Kennedy went outside to address them in the market square where, in unscripted remarks delivered through a megaphone, he told the crowd: “We’re on the move”.

There were also impromptu speeches from Sir Menzies Campbell, Baroness Williams of Crosby and the Lib Dem peer Lord Oakeshott of Seagrove Bay.

Anne Campbell is defending Cambridge for Labour with a majority of 8,579 but the Lib Dems have targeted the seat to capitalise on student unrest over Iraq and top-up fees.

Support for the Lib Dems has picked up since Charles Kennedy put Tony Blair’s honesty and the war at the centre of his campaign.

The latest Times/ITV News tracker poll puts the Lib Dems two points higher at 21 per cent compared with the day before. Labour is down one point to 40 per cent, with the Tories two points lower at 31 per cent. Other parties have gained one point to 8 per cent, their highest level so far in the campaign.

Mr Kennedy said that Mr Sedgemore’s defection was a pivotal moment. Michael Howard’s low rating showed that his party could not win, undermining Labour’s argument that voting for it would let in the Tories by the back door.

The tracker poll is undertaken over four days, with a quarter new every evening. The most recent interviews were on Monday evening, after a day in which arguments over the Iraq war had dominated the headlines. One day’s small shift should not be exaggerated, but it suggests that highlighting the war may help the Lib Dems. There is, however, limited damage to Labour, which retains its strong position.

At the rally in Cambridge, Mr Kennedy said that his party was heading for its highest level of support for a generation.

He said: “The Liberal Democrats have grown in strength throughout the first part of this campaign. We will gain further support over the next ten days. We look forward to going into the next Parliament with significantly more parliamentary seats.” Using language that was noticeably more bullish, he said that many leading Tories could lose their seats to the Lib Dems.

Mr Kennedy also defended his leadership, saying that his goal was to build on party successes, election by election.

He had earlier faced questions on whether the defection to his party of a left-wing MP confirmed charges that the Lib Dems had positioned themselves to the left of Mr Blair. Mr Sedgemore, a longstanding critic of Mr Blair, accused him of “stomach-turning” lies.

Mr Sedgemore, who has stood as MP for Hackney South & Shoreditch, said that he was among a group of Labour MPs who had agreed to leave after the election. Instead he decided to go further and join the Lib Dems, spurred by an invitation to speak at the Oxford Union last night, where he planned to announce his move.

The defection trumped a planned Labour announcement that Jonathan Simpson, a Lib Dem councillor in Camden, North London, would join Labour.

Populus interviewed a random sample of 1,427 adults aged over 18 by telephone between April 22 and 25. Interviews were conducted across the country and the results have been weighted to be representative of all adults. Populus is a member of the British Polling Council and abides by its rules.

For details see www.populuslimited.com .

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