Video: What should Gordon Brown do now?

The Conservatives were increasingly confident this afternoon that massive Tory gains in local elections across England and Wales would be capped this evening by victory for Boris Johnson, their colourful candidate for London Mayor.

With the outcome of the London vote due by 10pm, David Cameron's party was already celebrating a 44-per cent share of the vote nationwide. Labour, on 24 per cent, were pushed into third place behind the Liberal Democrats on 25 per cent, losing more than 300 council seats across England and Wales.

It was Labour's worst performance since the 1960s and a humiliation for Gordon Brown on his first proper electoral test as Prime Minister.

But victory in London would cap it all for the Tories. This afternoon, a senior Conservative source told the Comment Central weblog that Mr Johnson, MP for Henley, was set for a clear win over Ken Livingstone, the Labour incumbent. He said that that Mr Johnson would not win on first preference votes "but it will be pretty close to that".

By mid-afternoon, information on first-preference votes appeared to confirm that view, showing Mr Johnson ahead in nine out of the 14 constituencies, with Mr Livingstone leading in the remaining five. Mr Paddick was in third place in each of the areas. About 40% of the ballots have been counted since the count began. A result is expected at any time from 8.30pm tonight.

Meanwhile, Labour backbenchers began to tear into the the Prime Minister for being out of touch. One MP described it as Mr Brown's "John Major moment", a reference to the drubbing received by the former Tory premier in 1995, two years before he was ejected from Downing Street by Tony Blair.

Voter turnout in the mayoral poll is believed to have been at least 45 per cent, which is around 10 percentage points higher than the turnouts in the 2004 and 2000 elections.

In the run-up to the poll, Mr Johnson enjoyed a narrow opinion poll lead, although one bookmaker, Paddy Power, today announced it was paying out on a Johnson victory, hours before the count was completed.

Mr Cameron spoke about his hopes for Mr Johnson during a whirlwind tour around Wales and the north of England after his party's resounding polling success. Both the Tory leader and Mr Brown, speaking at a press conference in Downing Street, said they had spoken to their candidates and "thanked" them for fighting strong campaigns.

The scale of Labour's defeat began to rebound on Mr Brown. Derek Wyatt, Labour MP for Sittingbourne & Sheppey, who has one of the smallest majorities in the Commons at 79, branded the disastrous election performance a "John Major moment". He added that his seat was already "sub-prime" and only required someone to "sneeze" for him to lose it.

"Gordon has committed spectacular own-goals and the public is punishing him for it," he said.

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