Labour candidate is on 51% to Conservative mayor's 49% after trailing for months, YouGov poll finds

This article is more than 8 years old

This article is more than 8 years old

The London mayoral contest came alive on Thursday as an opinion poll showed Boris Johnson falling behind his rival Ken Livingstone and pollsters said the race was too close to call.

A YouGov poll showed that the Tory incumbent, who has been tipped to win re-election, had seen his lead against his Labour rival disappear 15 weeks before the capital goes to the polls on 3 May.

Livingstone edged ahead to take a 51-49 lead in the poll, and Johnson's spokesman said the poll would be "sobering" for the mayor's supporters. "Boris has never taken Londoners for granted," he added.

YouGov polled a larger sample than usual – 1,349 adults – between 10 and 16 January. The organisation has a record of reliability in polling London politics.

Of those polled, 46% said that, in a first round of voting, they would back Livingstone, 44% said they would back Johnson and 7% backed the Liberal Democrat candidate, Brian Paddick.

With Paddick eliminated, the second round votes appeared to fall evenly between Livingstone and Johnson. The last time YouGov conducted a poll of Londoners' voting intentions, in June 2011, Johnson had enjoyed a 54-46 lead.

The poll shows Labour voters who had been prepared to vote for the Tory mayor are now reconsidering. Last June, almost a quarter of Labour voters said they would choose him, but the latest figures have seen that number halved to 12%.

Those who see Livingstone as in touch with the concerns of ordinary people has risen from 37% to 40%, while the number for Johnson has fallen from 20% to 13%.

The YouGov president, Peter Kellner, said: "This is a huge change and, allowing for sampling error, the race is now too close to call.

"It amounts to 100,000 Labour voters switching back from Boris to Ken. It looks as though Ken Livingstone's promise to cut fares on buses and the tube has made an impact."

"The facts have changed, so I have changed my mind. Throughout last year, I regarded Boris Johnson as the likeliest winner of London's coming mayoral election. Boris's new year problem is that he is seen as increasingly out of touch.

"That said, it remains a significant achievement for Boris that he is still in the race. London is a Labour city."