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New poll puts Boris Johnson 12 points ahead

A Populus poll for The Times shows - in the first round of voting, Mr Johnson has 46 percent, while Ken Livingstone has 34 percent.

The Green party candidate Jenny Jones is in third place with 6 percent.

Brian Paddick the Liberal Democrat candidate has five percent, along with Siobhan Benita the Independent candidate.

UKIP's Lawrence Webb polls three percent, while the BNP's Carlos Cortiglia has one percent.