Boris the crowd-pleaser, fighting to his last gasp

That might have been a mistake. M Ferniou explained that among London's estimated 300,000 French speakers there is a huge potential vote. European union nationals who pay council tax can take part in the London elections and, he said, many will.

The venue was the Royal Thames Yacht Club, a teak-panelled haven on Knightsbridge, overlooking Rotten Row and decorated with fine portraits of famous boats and distinguished members, including the Duke of Edinburgh, painted in his yachting heyday. The room was packed with close to 300 people and they gave Boris a polite, but restrained, welcome. That was to change. He launched into his set-piece speech, delivering promises on cutting crime, providing homes for those who could not afford them, improving transport.

It was the usual election campaign fare. Then Boris began speaking in French. It was a touch jerky but he spoke clearly and with a passable accent. The regime of "Monsieur Leavingsoon" he said, was "pourri" - rotten. Change was needed - "Voilà! Je vous conseille - votez moi!"

It brought the house down. Suddenly, the tiredness was gone and Boris was taking questions, firing back answers on everything from introducing a rent-abike scheme (like the one in Paris) to an amnesty for long-stay illegal immigrants.

When it was over they clapped and cheered. Boris had managed to combine a star-quality performance with serious politics. It was a potent mix that even a month or two ago seemed unlikely.

Iain Dale, the political commentator and blogger, said the change has been remarkable: "I wasn't sure about Boris at first," he said. "I thought: 'Is this going to work?' He did make some disastrous mistakes but I don't get the impression his team are taping his mouth up now. He seems to have grown into the role. Boris can walk down a street and a crowd will gather round him. That's crucial. People see him as someone who is not a machine politician and he appeals to those who may not even have thought of voting."

A swift straw poll among the Francophones suggested many who heard him at the Royal Thames will vote for him. "I like him," magazine director Sabine Vandenbroucke told me. "He's a great character and he has good ideas."

Perhaps. The important lesson from Boris's evening with the French and Belgians was that, even knocked out by a cruel timetable, he can bounce back with energy and conviction, at least in that company. This, after all, was a constituency to which Boris could relate. Many of the expatriates hold down big jobs in the City. They are part of an elite with which Boris feels comfortable.

But London is not composed entirely of elites. What of the nitty-gritty of London life? Yesterday morning Boris took part in a radio debate with Ken and Lib-Dem candidate, Brian Paddick, for the BBC's Asian network. It was staged in a cafe in Stratford and it seemed to go quite well for Boris until he tackled Paddick, the former police commander in Lambeth, over his "softly softly" policy on cannabis. It had not been effective, Boris said, and it had given out the wrong signal to children.

PADDICK has proved himself a sharp performer in this campaign and he came back with a verbal rapier thrust. During his time in Lambeth, he said, police had seized 110 per cent more cannabis and made 20 per cent more arrests for hard drugs than before.

Boris was at a loss. His experience of the back streets of Brixton can only be guessed at and he had nothing with which to parry the ex-cop's attack. He mumbled an apology. "In that case Brian

... I'm sorry," he said. "I misunderstood you. I will happily withdraw that."

Boris has spent months getting on top of his subject. He has pored over reports and analyses of transport policy, housing policy, crime fighting and everything else that goes with the job of mayor. But he is unlikely to match Ken's grasp of detail on any of this and, from yesterday's performance, it would be folly to go head-to-head with Paddick on crime. And while he seems to have found a persona that combines his innate showbiz with an ability to inspire confidence on serious issues, he still lacks the sharpness for which Ken is justly renowned.

Witness the Newsnight debate of 10 days ago. Boris seemed wooden when he delivered his pitch; a self-conscious head boy among some very grown-up people. At one point he said he wanted to build "lots more wonderful new houses". Jeremy Paxman spared him no quarter but the lowest moment for the Boris camp came when, in a rare lapse, Ken offered up his jugular.

Ken had been forced on to the defensive over the appalling safety record of bendy buses and the horrific death of a passenger who was dragged under one as he got off. For reasons known only to himself, Ken blurted out something about the dead man being intoxicated and "massively over the limit".

Here was an opportunity for Boris to come back with what most people watching at home were thinking when they heard Ken's outburst - shame on you! To defend a political decision by blackening the name of a man killed in a tragic accident - one of many on Ken's beloved bendies - was a low blow, even for a streetfighter like Ken.

But Boris let it go. Does he lack the killer instinct that is so vital at this level, or has his metamorphosis produced a man whose ideas of statesmanship include a notion that you don't stoop to the level of your opponent?

Stephan Shakespeare, the pollster and co-founder of YouGov, thinks Boris has indeed changed: "He is more centred. You see now someone who is thinking clearly and getting a serious message across. There was a cloak of buffoonery, but he seems to have cast it aside."

WILL it be enough to bring the change at City Hall many feel is overdue? Shakespeare noted that with a strong incumbent like Ken, the challenger has to be a long way ahead at this stage. As polling day nears, he said, the electorate becomes nervous. The idea of change becomes less attractive. What if it means change for the worse?

Many may worry about who will do the top jobs. Why doesn't Boris name his team? The answer is - he can't, for precisely the same reasons that hampered Ken in 2000. The reality is that behind the scenes a transition team has been quietly put into place and a range of advisers, including experts on the City and arts, has been lined up. But the executiveswho have been identified for the vital roles in running London are already in high-powered positions and could hardly be expected to reveal their intentions ahead of an election that has yet to be won.

The list includes more than half a dozen executives from the very top drawer. An indication of their standing can be gauged from the announcement that Barclays chief Bob Diamond has already accepted the job of running Boris's proposed Mayor's Fund.

Boris may be ahead but no one can the predict the result of a contest that everyone agrees is too close to call. We can be sure of something that may have been in doubt before: Boris badly wants to be mayor. Those close to him say it would be a mistake to imagine his former playful demeanour was a sign of ambivalence. "He believes he can win this," one said. "He is going to fight to the last gasp."