Does anyone know who’s winning? On Monday, according to YouGov, it was Boris Johnson by a massive 13 points. But on Wednesday, according to Ipsos-MORI, it was Ken Livingstone by one, prompting The London Paper to dub him 'Comeback Ken'. So, is Ken coming back or is he a goner? Londonist is as baffled as everyone else but maybe the past week contained some clues about which way the tide is going.

On Tuesday, Newsnight hosted only the second televised debate between Livingstone, Johnson and Paddick (the first was way back in January). There was no clear winner, yet of the two frontrunners Livingstone fared best, as Tory blogger Iain Dale quietly acknowledged, and betting man Mike Smithson agrees.

“Normal people don’t watch Newsnight,” scoffed a key member of Team Boris when we mentioned this to him. But if he has a point it applies less to Question Time and to BBC London, both of which host their own mayoral debates soon. For Johnson, much depends on how well he holds up under the harsh, impartial scrutiny these occasions will subject him to. Though he’s clearly worked hard to master the London brief, the contrast between his celebrity appeal and that of Livingstone’s hardened experience may soon become more apparent to voters who’ve yet to make up their minds.

Meanwhile, the struggle on the streets has intensified. Johnson has been flattering the outer boroughs with his presence from the start of the campaign, to good effect. Now, Livingstone has begun touring the inner city, enjoying warm welcomes in Lambeth and Hackney. If he can stir such core support and reassure the undecided that he’s the only serious option, then he may triumph even if he’s trailing just now. As Tony Travers wrote on Monday, “Never write him off.”

By Dave Hill

Read more from Dave over at the Guardian, and on his mayoral blog.