THE dying days of the election campaign developed into a bitter battle between Labour and the Liberal Democrats last night as Charles Kennedy called on voters to deny Tony Blair another three-figure majority.

After Mr Blair and Gordon Brown blitzed marginal seats to warn electors that supporting the Lib Dems would let in the Conservatives by the back-door, Mr Kennedy retaliated by demanding an end to tactical voting to help Labour.

In recent elections there have been unofficial pacts under which Lib Dem voters without any hope of securing an MP of their own colours have tactically supported Labour to keep out the Conservatives. But Mr Kennedy told his supporters that they should no longer indulge in such behaviour in seats that the Tories held or where they were challenging Labour.

He said: “If there was ever a tacit understanding in days gone by, that is certainly terminated. What I would say to people who are inclined to vote Liberal Democrat is go and vote Liberal Democrat.”

His words echoed the earlier Conservative campaign tactics that voters should “send a message” to Mr Blair by preventing him getting another landslide.

Mr Kennedy was reacting to the increasingly ferocious Labour campaign against the Liberal Democrats. Mr Blair, embarking on a tour of marginals with the Chancellor, said their economic plans “simply do not stack up”. But his message as they travelled round four South East seats taken by Labour for the first time in 1997 was that a protest vote for the Lib Dems could let in the Tories. He said that Labour had to be careful of people looking at the polls and saying “it doesn ’t really matter if I drift off and vote for someone else”.

He added: “There are three ways to get a Tory MP. One is to vote Tory, one is to stay home, one is to vote Liberal Democrat. Take nothing for granted. Unless people come out and vote Labour, it is a Tory government they will wake up to on May 6.”

The tour and a fresh election broadcast tonight are being accompanied by the contentious and arithmetically questionable claim that if one in ten Labour voters does not vote, the Conservatives will win. Mr Kennedy said it was clear that the Conservatives could not win the election and dismissed Labour’s claim that a vote for the Lib Dems in several dozen marginal seats could let Michael Howard into No 10.

He told supporters in Dorset: “The fact is that the Conservatives nationally appear to be out of the race in terms of this election. But we don’t want Tony Blair back with some sort of three-figure majority where he can do what he likes, irrespective of opposition parties, never mind opinion within his own party. It all points to a decisive vote for the Lib Dems.”

Mr Kennedy pointed to evidence from parliamentary by-elections in the past two years, which showed Lib Dems coming from third place to win in Brent East and Leicester South and challenging Labour closely in Birmingham Hodge Hill and Hartlepool.

In another attempt to win Labour votes, he appeared at his election press conference yesterday with Greg Dyke, the former BBC Director-General and a longstanding Labour supporter and donor who has now switched to the Lib Dems. Mr Dyke said he could no longer support a Labour Party led by Mr Blair.

Mr Howard shrugged off suggestions that he was heading for defeat, telling activists in Manchester he was “very, very confident” of the outcome. He said: “I believe our message is getting across. People know what is needed for the future of our country and they have a very clear choice on Thursday.All my thoughts and my actions are focused entirely on that objective.”

The Labour-Lib Dem battle is given added spice by an ICM poll for The Guardian today, which suggests that Labour could have more trouble in its battleground seats than the national polls suggest.

Data from ICM’s campaign polls shows that Labour’s share of the vote in its 108 key seats, where it is facing a strong Conservative, challenge is down from 47 per cent in 2001 to 41 per cent now, while the Tories have maintained their share of the vote at around 36 per cent.

A survey in Baroness Thatcher’s former seat of Finchley & Golders Green shows that the battle is neck-and-neck, even though it is only 42 on the Tory list of target Labour seats.

Times Recommends

• Time-worn Freddie gives up Test matches
• Brighton company 'involved in cyber attack'
• The art of survival: it’s all in the mind