No reason to back him

There is no reason for any socialist to vote for him as London mayor. If he loses, it's his own fault. Let him learn his lesson.

The above, or approximations of it, can be heard at left meetings in London and beyond and surface from time to time in the letters columns of our paper.

There are many criticisms that can be made of Mr Livingstone and, even if every single one of them was justifiable, the fact is that his defeat in the London mayoral election on May 1 would be an unmitigated disaster for working people, national and religious minorities and the poor.

For him to lose to any Tory would be a setback for the left but to lose to a well-heeled, arrogant, far-right racist buffoon would be cataclysmic.

According to recent opinion polls, Mr Livingstone could be up to a dozen points behind Boris Johnson, who is backed by London's only evening newspaper and by much of big business.

For all his carefully cultivated efforts to promote himself as a bit of a character - think Billy Bunter without the extra weight - Mr Johnson is a nasty piece of work.

His comments on black people speak for themselves, as much as he tries to pass them off as a joke.

Compare that with a drop of 55 per cent in racially motivated crimes since 2000, with Mr Livingstone as mayor.

The mayor's single-minded promotion of multiculturalism and support for LGBT organisations has assisted a dominant live-and-let-live attitude among Londoners.

His promotion of affordable housing and public transport, especially on the buses, has helped poor people, as has his insistence on a London minimum wage.

And his work to promote cycling and public transport, along with the congestion zone and low emission zones, is improving air quality.

Although his opposition to the Iraq war and outspoken criticism of George W Bush cannot change government policy, they contribute to a progressive public mood that would be stifled by Boris Johnson.

There is no use blaming Mr Livingstone for the fact that Londoners are not living in a socialist society already. His project is reformist, which is the maximum that can be achieved in one city in a capitalist society.

By all means criticise him for his wrong line over Jean Charles de Menezes and give him a good kicking over his failure to unite with the rail unions to campaign to keep all of the Tube in public ownership.

But, as important as these issues are, they do not make the case for Boris Johnson to be elected.

There are times for protest and denunciation. There are also times to swallow deeply, realise the scale of what is at stake and put aside all divisions to unite the labour movement in fighting for what is possible and desirable.

May 1 is one such day, when Greater London's labour and progressive movements must unite to return Ken Livingstone as London mayor.