Boris races ahead in mayor poll

The most detailed survey yet puts the Tory candidate 12 points ahead, suggesting many Londoners feel it is time for change.

The YouGov poll has Mr Johnson on 49 per cent, the Mayor on 37 per cent and Liberal Democrat candidate Brian Paddick on 12.

Mr Livingstone has been rocked by allegations of cronyism and corruption at City Hall and the London Development Agency leading to the resignation of key aide Lee Jasper.

His attempts to fight back by discrediting Mr Johnson's transport plans and questioning his competence appear to have had limited impact so far. But polling experts believe the findings say more about the view that Mr Livingstone has over-stayed his welcome than they do about the

success of Mr Johnson's efforts to rebrand himself as a serious politician. YouGov questioned a representative sample of 1,005 Londoners online between 12 and 14 March. A total of 17 per cent said they did not yet know who they would support, suggesting there was all to play for.

Mr Livingstone's vote, according to YouGov, has fallen from 44 per cent in January to 39 per cent in February to 37 per cent. Mr Johnson's has gone from 40 per cent to 44 and 49 per cent today, while Mr Paddick went up from eight to 12 per cent but this month stayed static.

The change can be explained by Labour voters deserting Mr Livingstone and by Londoners who have no clear political allegiance switching from the Mayor to Mr Johnson. The vote share of the minor parties was more squeezed than ever.

In today's survey, Mr Johnson was particularly popular among women voters. He also picked up 53 per cent of the 18 to 24-year-olds, compared with Mr Livingstone's 41 per cent.

He was also ahead of the Mayor among 25 to 34-year-olds and 35 to 44-year-olds and in the over-55s, where he got 53 per cent compared with Mr Livingstone's 29 per cent. The only age group in which the Mayor came ahead was 45 to 54-yearolds where he won 47 per cent to Mr Johnson's 38 per cent. Exactly 50 per cent of the ABC1 social group said they would vote for Mr Johnson, while 33 per cent backed Mr Livingstone and 14 per cent Mr Paddick.

The Tory challenger could win the race on first preferences because he has a realistic chance of taking more than 50 per cent of the vote. If nobody achieves 50 per cent, the number of second preference votes are added. Mr Johnson got 20 per cent share of second preference votes to Mr Livingstone's 17 per cent.

A spokesman for Mr Johnson welcomed "these encouraging results," adding: "There is still a long way to go, however." A spokesman for the Mayor said: "If the agenda of the election shifts to the key issues for London then Ken will win."

A poll for the Greater London Authority says 61 per cent of Londoners support the Mayor's plans for a £25 congestion charge on 4x4s.