A Liberal Democrat, Norman Baker, won Lewes, in East Sussex, in 1997 after 10 local Labour members were expelled from the party for recom mending an anti-Tory alliance in the polling booth. A swing of less than 2% could hand the seat back to the Tories, who stayed at home in large numbers four years ago.
A letter today to the local newspaper, the Sussex Express, signed by 22 people describing themselves as supporters of both Labour and the Greens, says: "Labour, Lib Dem and Green supporters have much common ground. We therefore urge all progressive Lewes people to vote for Norman Baker in the coming election."
Labour officially remains opposed to tactical voting, even though some Labour supporters, such as the leftwing singer Billy Bragg, are organising websites to trade votes between anti-Tory parties in marginal seats.
Arthur Hammond, the Labour agent in Lewes, said: "Any Labour members supporting another candidate would be subject to expulsion." The party members who supported Mr Baker in 1997, some of whom signed today's letter, still have a year of their five-year expulsion to run.
Last night Mr Baker insisted the renewed call for Lib-Lab solidarity in Lewes had been done without his involvement. "They are falling in with the public mood," he said. "Last time they wanted to beat the Tories, and it's the same feeling this time because people don't want William Hague."
The Lib Dem leader, Charles Kennedy, turned party policy on its head earlier this week by openly encouraging tactical voting, instead of insisting that every vote counts whether or not it helps to elect an MP. Tactical voting won the party its most spectacular byelection victory of the parliament, in Romsey, Hampshire, when a Tory majority of more than 8,000 was overturned.
Reports of informal local pacts in seats won by the Lib Dems in 1997 are being fuelled by claims from seats such as Lib Dem-held Sheffield Hallam, where Labour activity so far is said to be minimal.
But Labour disputes the psephologists' analysis that the Tories lost up to 35 seats, to Labour as well as Liberal De mocrats, through tactical voting. It is also reckoned that anti-Tory sentiment is weaker than it was four years ago, and at least some of the party's supporters who sat on their hands in 1997 will return to the fold this time.
But tactical voting could be significant in London, where the Lib Dems are defending six seats, five won at the last election. Launching their London manifesto, the Lib Dems said the Tories' problems over race, together with disaffection from some Labour supporters because of slow progress on public services, could hand them two more. Among their targets is Orpington, in Kent, a seat they last won in a byelection 40 years ago.
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