Boris’ jokes face a serious test in 2012

Boris' ability to make people laugh is a formidable, if unusual, political weapon. The way he wields it in next year's mayoral election will be a critical test.

Another Tory conference, another triumph for Boris. He is the darling of the Conservatives and the secret gnawing frustration of the prime minister. But how high can his unique approach to politics take him? Is he inherently limited by his scattergun patter? Or can he, as some are beginning to wonder, go all the way?

Boris' comic capital ranks so high he is funny whether he means it or not. Sometimes it means he can do no wrong. A 'rally for Boris' held last night on the conference fringe in Manchester summed this up. Despite having been kept queuing for ages, the audience refused to become irritated when he failed to appear after an introductory video. When the introductory video was played, desperately, a second time, they just laughed. And when the flustered mayor finally made a rather ridiculous entrance halfway through the third video repeat, poorly lit as the video played on, they erupted in applause. Truly, he can do no wrong.

Why? Because Boris' audience had come to be amused and was determined to find him funny, regardless. The mayor's humour appears unintentional, the side-effect of his thoroughly funny personality. But those who have followed his career closely say he is never unaware of the effect he has. He will always play up to the crowd. As he learned many years ago, the advantages of embracing his persona far outweigh the disadvantages. So he doesn't hold back.

We got glimpses of his technique in his speech to the party conference this morning. When choosing which pieces of information to impart to their audience, no other Tory minister would select a fact like the colour of the Olympic velodrome, whose "rosy hue" stems from its being rubbed in rhubarb. Nor would they utter words like: "I'll tell you who stood up for London - that chap who sat on a looter's head!" Nor would they spot their party leader in the audience and say: "There's Dave!"

But the big platform speech is actually rather limiting for someone who specialises in the unexpected, impulsive train-of-thought that only a less formal address can bring. Often this really is genuine. When a Tory councillor said she had been trying to get hold of him for ages, but complained that he was protected by a "ring of steel" at City Hall, he responded by thinking on his feet. "You've penetrated my defences!" he said exultantly, before struggling to come up with a decently amusing metaphor. Eventually he thought of one, saying triumphantly: "Like Frodo Baggins!"

At other times this approach may be more cosmetic. He appeared to distract himself when he mentioned Gandhi, saying in an aside that the ex-Indian leader happened to be an "ex-barrister from Temple". That's exactly the sort of thing close Boris followers suspect he's used on dozens of occasions. He keeps them up his sleeve for exactly this sort of occasion.

This technique is at the heart of Boris' approach. And it's important because there's a chance this impression of madcap mental veering to and fro could be given more free rein in the 2012 race. During the 2008 mayoral campaign Boris was kept on a tight leash. He constrained his wandering brain to the banalities of normal politics-speak. But next year, having refined and adapted his style, there's a chance his handlers will be happy letting him off the leash.

Already we're seeing signs of him being able to get the message across while keeping some of his unique style of delivery. For example, where a duller politician might have flagged up the success of his reforms to London public transport system vehicle stocks, Boris observes that by the end of his mayoral term "the last breeding pair of bendy buses will have departed to the happy breeding ground of some Scandinavian airport... or the city of Manchester." It gets the message across, but keeps the style.

The theme of his campaign, putting the village back into London, is tailored to reflect his approach, too. "What could be more ebullient of a village than all these people who patiently shouldn't be in charge of a bicycle weaving their way around London?" he asks, and who can deny he's right? Flowery language is effective in combating Ken, too, who he portrays sitting at the bottom of the Marianas Trench, "stewed in bitterness and bentness".

Even the mistakes, the broken promises, can be covered up. "I've kept all my pledges," he said shiftily, before adding very quickly and in a low tone: "Well, almost all of them. Except for one, Blackwall tunnel, which proved technically very difficult." Such is the sheer weight of his charm that it becomes horrifyingly easy to forgive him. If this is deployed on the doorstep, it's hard to see how it will be combated.

Only there is an obvious way of fighting it, isn't there? By simply pointing out that the mayor is a joke, not a serious man for serious times. If as expected he does deploy his humour more than before, next year's election will test that to the full. And if it applies to the City Hall job, its significance is magnified tenfold when it comes to Downing Street. The well-placed bon mot risks appearing flippant or even dismissive when dealing with real-life tragedies. "These are tough times, folks," as he put it yesterday at the start of a section about spending cuts, might not sound quite right when coming from the steps of No 10.

This is Boris' challenge. If he wins re-election next year in a campaign different to 2008's, where his personality takes centre-stage rather than being suppressed, he will remain in the running for the ultimate prize, the party leadership, whenever David Cameron steps aside. For years, the idea seemed laughable. But that attitude has slowly been undermined by his performance in City Hall. It could be banished altogether if the 2012 campaign goes according to plan.