By Nyta Mann BBC News Online political correspondent

One person was even more delighted than Nicky Gavron when she won Labour's contest to choose its candidate for London mayor: Ken Livingstone, the incumbent she is supposed to unseat.

Put bluntly, the Livingstone camp is confident that come the 2004 London mayoral election, Ms Gavron will put up a far weaker fight than Tony Banks, her rival for the nomination, would have done.

Many of the activists in the London Labour Party and its affiliated trade unions who backed her made no secret of the fact they were doing so purely to maximise Mr Livingstone's chances of being re-elected.

Ken Livingstone: Would have faced a more vigorous campaign from Tony Banks

In fact it would not be at all far from the truth to say that earlier this year, when Labour rejected Mr Livingstone's application to rejoin his old party and enter the contest for its London nomination, Ms Gavron became his proxy in that race.

She consulted the mayor ahead of her decision to seek the Labour candidacy - and from the off, keeping the Tories out of City Hall was her central message, rather than getting Labour in.

Aides to Mayor Livingstone assisted her throughout her selection campaign, helping to draft her literature, giving media advice and attending hustings meetings to keep a guiding eye on how their horse was doing.

Mr Livingstone himself voiced his strong support for his deputy mayor becoming his opponent at the election.

Prize

So all in all, those Labour Livingstone supporters disappointed at not having the chance to choose him as their official candidate knew pretty well who to swing behind as the next best thing.

And hence Ms Gavron, whose profile is not much higher within Labour than it is among Londoners at large (i.e. as low as a tunnel on the Northern Line), has won the prize of taking him on at the ballot box.

Even some of Mr Livingstone's closest supporters have voiced reservations that the "cynical chicanery" behind the whole business looks bad when set against the overarching David-and-Goliath narrative of the last mayoral battle.

Re-election nerves

But there is method behind Mr Livingstone's meddling.

After more than two years as mayor, chief among public perceptions of his reign so far are that the pigeons he sought to banish from Trafalgar Square are still there, the Tube runs no better than it did before his election, and the traffic is a hell of a lot worse.

Crowning all this is his congestion charge scheme, due to come in next February and the cause of intense nervousness among the capital's drivers and within the mayor's own office alike.

Add to that the fears of a low turnout working against his "soft" vote, and London's mayor is understandably anxious to minimise the scale of any obstacle in the way of his re-election.

No doubt Nicky Gavron would actually like to be mayor of London. Unquestionably she is bursting with policy ideas sincerely aimed at improving life in the capital.

But it would be a mistake to believe that either of these two things played any great part in landing her the Labour candidacy for London mayor.