by Laura Kuenssberg
BBC political correspondent
Boris Johnson attempted to woo the crowds
A surreptitious thumbs up gave it away.
As Boris Johnson took his seat after his campaign launch speech, the gesture to his old friend David Cameron, suggested that at least the candidate himself thought he'd made a good fist of it.
And the crowd of Conservative activists seemed to agree. Boris' crowd of young supporters in colourful "Back Boris" T-shirts, whooped and cheered after Mr Johnson's fifteen minute speech.
He talked of his desire to get London moving, improving public transport, providing affordable housing, and mostly, his passion for cutting crime, ending the violence that in his view, blights some of the capital's communities.
And the team had chosen a fitting location - a community centre in Edmonton nearby to where a young man recently lost his life to violence.
Mr Johnson was welcomed by the community activist, Ray Lewis, founder of the Eastside Young Leaders' Academy, whose life's work is helping troubled young men, and introducing discipline into their lives.
I asked him, not for the first time, if he really thinks that after a career where he's been accused of devoting his energies to playing the clown, people can really take him seriously
As Mr Johnson spoke, the crowd, and his boss, looked on, almost adoringly for the most part.
Lynton Crosby, the Australian campaigning guru, lurked around the edges of the audience, trying not to be caught on camera.
An election veteran, and the man behind Michael Howard's failed general election campaign in 2005, he'll take nothing for granted.
But the "Back Boris" team were certainly in chipper form.
Perhaps they, and he, can't quite believe their luck. A member of the team confirmed to me today that they simply had not expected to be ahead in the polls at this stage of the campaign.
Polls are an inexact science, and certainly in this election where second preferences count, traditional percentage based polling gives nothing like a guarantee.
Yet, another poll today suggests that the Conservative candidate is consolidating his lead.
I asked him, not for the first time, if he really thinks that after a career where he's been accused of devoting his energies to playing the clown, people can really take him seriously.
But again, he answered that he's really serious about the job - determined to do it and desperate to make a difference to London.
Certainly, since the campaign has been in full swing he looks different - the suit more sober, and the hair less wild. There are still a few laughs, but not quite so many jokes.
But there's something about his demeanour, a twinkle in the eye, a sideways glance every now and then that suggests there's something else burbling underneath - a quip longing to escape, a joke uncracked.
There is something about Boris in campaigning mood that's buckled down.
Can it stay that way in a campaign that will get tougher and tighter?