The eve-of-poll survey by Populus for The Times, based on interviews with 2,042 adults on Monday and Tuesday, shows that a third of voters have made up their minds only during the course of the election campaign. Among those, 43 per cent back Labour, 29 per cent back the Lib Dems and 21 per cent back the Tories.

Looked at another way, 22 per cent of Lib Dem supporters made up their minds in the past week, as did 19 per cent of Labour supporters, but only 11 per cent of those intending to vote Tory.

The undecideds are also moving away from the Tories. Among those who give a preference, a tenth of all voters, 41 per cent, are leaning towards Labour, 24 per cent towards the Tories and 26 per cent to the Lib Dems. The poll shows how more than half of each party’s voters, a range of 50 to 56 per cent, are supporting them for negative, not positive, reasons.

More than a third of voters (36 per cent) would prefer a Labour majority, compared with 18 per cent who want a Tory majority, and nearly as many (18 per cent) who want a Lib Dem majority.

More than three quarters of the electorate (78 per cent) expect a majority Labour government. This includes more than three fifths (64 per cent) of Tory supporters. More than half the public (53 per cent) and of each party’s supporters expect a Labour majority of less than 100. By contrast, 8 per cent of voters expect a Conservative government, including 26 per cent of Tory supporters.

When asked which of various factors had the biggest influence on deciding their votes, 25 per cent named party positions on public services such as the NHS; 17 per cent named their opinion of Tony Blair; 14 per cent named immigration and asylum-seekers; 13 per cent named tax and public spending; and 7 per cent named a negative opinion of one of the other parties. More than a half of Labour voters (53 per cent) say that they would prefer Labour to be re-elected with a small majority than with another landslide.

Fewer than 38 per cent agree that, if Labour wins, Tony Blair should stand down early in the next Parliament, making way for Gordon Brown. Some 56 per cent disagree. Moreover, 70 per cent of Labour voters say that they think of themselves more as supporters of new Labour than old Labour.

Tory supporters back Michael Howard and his campaign. More than four fifths say that the Tories look like “a 0credible party of government again” and that, even if he loses the election, Mr Howard has “done a good enough job to carry on as party leader”.

Interviews were conducted across the country and the reuslts weighted to be representative of all adults. Populus is a member of the British Polling Council and abides by its rules. For more details, see www.populuslimited.com

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