Independent candidate Siobhan Benita is something of an enigma in this year's mayoral race. Materialising as a complete unknown a few months ago she has, in her own words, "flummoxed" the political elite with her soaring poll ratings set against an apparent lack of any serious backing, funding or party-political allegiances.

She has been banned from appearing at any broadcasted mayoral hustings, and having never before held a publicly elected office, she's been criticised by some as being too inexperienced for the job.

But with George Galloway's 'Bradford Spring' still fresh in the memory, and Boris and Ken's slanging matches becoming more and more tiresome with every passing day, Benita argues that the time is right for a departure from mainstream party politics at City Hall.

"I want to be political, I just don't want to be party political" she tells me, reclining on a sofa in her ad-hoc campaign base in the lobby of the Royal Festival Hall. "I think the opinion polls show people have never been this fed up with party politics - they don't trust them and they don't believe what they say any more.

"When you look at Ken and Boris, they're always fighting old party political battles, which gets in the way of actually doing the right thing for London."

She is right, of course. Politics in Britain, like in many other countries, is a never-ending battle between the two opposite sides of our political spectrum. And with her easy demeanour and calm, friendly tone cast stark against the cacophony of screaming school children and coffee-slurping tourists in the Festival Hall, I am finding it hard not to like - and believe - Benita myself.

But although it may not be perfect, our party political system does at least allow the public to know fairly easily what the fundamental leanings of a given politician are.

With such a broad range of policies, which include her backing of Heathrow expansion and a pledge to bring more affordable housing to London, she does admit to having some trouble trying to get people to understand where she sits on this political spectrum.

"People do want to know where you sit on that scale of things. I have always voted Labour, but I don't know how I'd vote in the next election because I honestly think that all the political parties have lost their way. I think they're in a kind of identity crisis and they're fighting over this space in the middle."

It is clear then, that Benita the politician is a left-leaning one, and having worked as a civil servant for 15 years, mostly under Blair and Brown, she is well acquainted with the political system. But the civil service is a politically neutral body, so unlike the other candidates she is in no way tied to Labour, or any other party.

During this campaign Boris has made much of the claim that he was able to secure more funding for London through his Conservative government connections, but Benita is quick to dismiss this as a flawed argument, saying "It's all very well Boris saying 'I've managed to get so much out of the treasury because they're my mates' - but what about when [the government] changes?

"As an independent you will always be able to have a more rational conversation [with the government] because you don't bring the party political baggage with you."

On the question of party financing, however, it is clear that the backing her competitor's enjoy does bring with it a huge war-chest of funds for campaign publicity.

And it is this which I find most intriguing about this election - bookmakers have slashed Benita's odds of winning from 500-1 to 25-1 in a matter of weeks, but without party backing her entire campaign has been run on a shoe-string budget - and she tells me this has led to some imaginative speculations about mystery benefactors, including the Blair Foundation, David Cameron and Richard Branson.

She laughs off my suggestion that Richard Branson himself might have thrown the odds by putting a big bet on her to win, but the point I'm trying to make is that bookmakers are not in the business of backing losers, and if there are in fact no errant billionaires burning up cash backing Benita at the bookies, then she must really be in with a chance.

And as I leave her grandiose adopted office on the Southbank, I can't help but think that if such an outsider as Siobhan Benita were to make it into City Hall at the expense of the megabucks political play-makers, then it must surely be a victory not just for her, but for democracy too.

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