Tony Blair is heading towards his final electoral test with Labour on 29 per cent, its lowest rating since he became leader 13 years ago and its most lowly position in the run-up to local elections for more than 20 years.

Today’s Populus poll for The Times suggests that Mr Blair will depart office after ten years as Prime Minister with one of his party’s worst-ever drubbings behind him.

Labour’s rating has sunk to a level previously seen in the early 1980s during Michael Foot’s troubled leadership.

But although the Conservatives have led for a year the survey suggests that their leader, David Cameron, has still not made the breakthrough to give him an overall majority at the next general election.

That is Labour’s only consolation as troubles mount. Two Cabinet ministers were forced to apologise to the Commons yesterday — Des Browne over the debacle in which the Iran captives sold their stories and Patricia Hewitt over the medical training row. Meanwhile, Gordon Brown faces a vote of no confidence in the Commons today over his 1997 decision to scrap tax relief on dividend payments to pension funds.

The survey, conducted over the weekend, shows the Conservatives on 37 per cent, maintaining an eight-point lead over Labour. Both were down 1 per cent on last month.

But it also shows that at least a third of voters are withholding their support from the two main parties, with the Liberal Democrat rating rising two points to 20 per cent, and 14 per cent of electors preferring other parties including the Greens, the nationalists and the United Kingdom Independence Party.

The poll suggests that voters will use the forthcoming elections for the Scottish Parliament, Welsh Assembly and English town halls to cast a verdict on Labour’s record overall.

The survey will make grim reading for Mr Blair and his successor. Labour has a similar level of support to that accorded the Conservatives under John Major at the same point of the 1992-97 Government.

But the Conservatives are nowhere near where Labour were at this point of the 1992 government. Then, Labour’s rating had risen to 44 per cent and remained at that level for the whole of the second half of the Parliament. The Conservative average in polls published this year is 38 per cent.

The steady rise of minority parties is a worry for both parties. The number voting for “others” has moved from 8-9 per cent at the last election to 10-11 per cent last November, and is now around 14 per cent. In the Times survey the Greens are on 4 per cent, the SNP 3 per cent, Plaid Cymru 2 per cent, UKIP 2 per cent, and the British National Party 1 per cent. Labour’s support has fallen lower than in any Populus survey for The Times, though three polls this year have put Labour on 29 per cent, including ICM last month. The last time ICM recorded Labour as low as 29 per cent was in April 1987.

The survey suggests that 39 per cent of those voting on May 3 will treat the election as an opportunity to cast a vote on the Labour Government’s record. Some 24 per cent say that they will treat it as a verdict on Mr Blair and 16 per cent on Mr Brown, with 14 per cent saying they will be influenced by local, not national factors.

Significantly, 30 per cent of Labour voters believe that the elections will involve people reflecting their views on Mr Blair, and 18 per cent think that it will be about Mr Brown as well as Mr Blair. Some 25 per cent of Labour voters think that it will be a verdict on the Government’s record.

Populus interviewed a random sample of 1,503 adults across the country aged over 18 by telephone between April 13 and April 15. The results have been weighted to be representative of all adults. For details go to www. populuslimited.com

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