Martin Bell was a well-known BBC international correspondent who became an MP in 1997 on an independent anti-sleaze platform against Conservative MP Neil Hamilton. He served one term and now works as a UNICEF ambassador. He lives in Hampstead Garden Subur

Martin Bell was a well-known BBC international correspondent who became an MP in 1997 on an independent anti-sleaze platform against Conservative MP Neil Hamilton. He served one term and now works as a UNICEF ambassador. He lives in Hampstead Garden Suburb.

For the first time in three campaigns the Mayoral election is a cliff-hanger.

It has a real buzz about it. It is a contest not between party apparatchiks, but between the only politicians in the land - reviled by some, beloved by others - with whom we are all on first name terms. This isn't Livingstone versus Johnson. It is Ken versus Boris. And I like the look of some of the other candidates, especially from the Greens and the Lib Dems.

The campaign has been exemplary in that it has been conducted mostly through public debates and in the media without costly and defamatory billboard advertising.

But I worry about London's principal newspaper. The Evening Standard has let its opinions spill over into its news coverage.

New Labour's experiment with elected mayors did not work out as planned.

In some places, like Mansfield, the people rose up against the Labour Party establishment, not once but twice.

In London, the party moved heaven and earth to stop Ken at his first attempt - even approaching me at one point - and failed.

He won more votes as an Independent than when they took him back into the fold.

London has benefited from having an elected mayor. It has had someone to challenge central government on our behalf.

It has had someone to act for us, and someone to speak for us, when things get out of hand.

The two main candidates seem to be blessed with more charisma than almost all other politicians combined.

One has more experience than charm (though he has that too), and the other has more charm than experience. I shall decide between them as I cross Big Wood on election day.

Someone else may get my first vote, but in that case Ken or Boris will get my second.

This is the advantage of the preferential system - you can vote to your heart's content on your first choice for Mayor, but you would do well to use your head to decide your second.