Melanie McDonagh: If Ken likes a drop before elevenses, I'm on his side

He's got a nerve. The Prime Minister has let it be known he is worried that Ken Livingstone might lose the London mayoral election on account of his drinking habits. Apparently Livingstone pitched up at Davos at the World Economic Forum "under the influence of alcohol". Gordon Brown, it was reported yesterday, now frets that if Labour loses the mayoral election, the blame will be attributed to him, not to Ken.

Well, the people of London just might want to vent their spleen at the amount the capital's population contributes in taxation, and the services they get back in return, by voting anything but Labour. The disparity between the two is so great that they're entitled to.

As for Ken Livingstone, there are scores of reasons to worry about his re-election – and if you hang on, I'll get round to a few – but they do not include drink. When the Channel 4 Dispatches programme presented by Martin Bright alleged that he drank whisky at 10am – as though this were comparable to the allegations about the misuse of London Development Agency funds – my sympathies swung right round to Ken. When it emerged that, while addressing the electors of Ilford, he was seen sipping "an amber liquid", my only thought was that he should, like my late granny, have taken the precaution of decanting it into a Schweppes ginger ale bottle.

The contest is too serious to be turned into a dispute between the puritans in Downing Street, bizarrely supported by Boris Johnson (teetotal for the duration of the campaign) versus the bon viveur. It takes attention from the decent reasons for worrying about Ken.

One is his imperial tendencies. Those who accused Livingstone of running City Hall as a private fiefdom had the wind taken right out of their sails when he cheerfully admitted on Radio 4 that this was the case. City Hall employees were his employees, engaged in promoting his agenda; not to be compared with civil servants. But it is untrue that the positive elements of his programme – campaigning against Gordon Brown's PPP proposals for the Tube, bringing in the original congestion charge and returning police to the streets – could not have been effected if the staff at City Hall behaved like normal public servants.

Those employees certainly should not, as Atma Singh is said to have done, be writing pro-Ken propaganda in office time. Council taxpayers in London should not be paying consultants – another Dispatches allegation – to smear Trevor Phillips, because his views on multiculturalism do not coincide with Ken's. And a man who employs 70 press officers is too grand for our good.

Then there is his weakness for big business. Where are the Trots in City Hall when you need them? Last week, the Green Party pointed out that Ken approved proposals for more than 50 shopping malls, while the number of small, independent London shops decreased correspondingly. Cause and effect.

Take his weakness for bombastic tall building. There were two in London when he took office; he has approved plans for about 20. His relationship with property developers ought to give the lie to the notion that he is dangerously left wing. What is more, he is steamrolling opposition from local authorities with powers provided by the Government.

As for the allegations about the misappropriation of LDA funds for companies associated with Lee Jasper, his race adviser, they're now with the police.

Given all this, why focus on his drinking? Boris Johnson got one thing right when he said Ken Livingstone was "drunk on power". That's the real problem.