It's raining in West London, and mayoral hopeful Siobhan Benita is running late.
Her car screeches to a halt outside Acton High School, mounting the curb. Benita springs out of the front seat joined by a small entourage – a PR woman (juggling/spilling four cups of coffee) and a camerawoman from a national newspaper.
A loose radio mic wire hangs down the side of Benita's neat, green, pleated dress.
"I'm never late," she apologises. "The first day of the campaign I take private transport, and I'm late." She pulls an embarrassed smile.
She looks and sounds like your typical political candidate.
Then you notice the black high heels.
And that's when you remember that this is her first stab at elected office. A seasoned political campaigner would never traipse the streets in three-inch heels.
But if Benita's feet are sore, she doesn't show it. She doesn't seem to care that she's new to this. And the polls seem to agree.
Although it would take a pretty big leap to say she could win, the latest YouGov poll gave her a three per cent share of first preference votes.
That puts her equal with UKIP and ahead of Green candidate Jenny Jones.
Her knuckles may not be reddened from years of door knocking, but don't expect her to apologise for it.
"I’m amused by the people who have criticised me," she says with a shrug. "It’s the kind of 'how very dare she come and do this'.
"But that’s my point. That is exactly what I’m trying to say.
"The mayor should not be reserved for party politicians who have done nothing but party politics.
"We need to have something else.
"Whether I’m just starting that conversation, we have to have different types of leaders coming forward.
"So when Simon Jenkins writes, 'She needs to start knocking on people’s doors', he’s missed the point of my whole campaign."
What do her fellow mayoral candidates make of her?
"Ken and Boris have both been very nice to me," she says.
"They’ve both been very polite.
"Boris quite jokingly said, 'If you ever did get on a TV debate then that would be it. You would wipe the floor with me, so I’m quite pleased that you’re not', which was quite nice."
But it hasn't all been butterflies and happy sighs.
"It’s ramped up," Benita admits, readjusting her ponytail.
"At the beginning, people thought I wasn’t going to make any impact. Brian Paddick has come out recently saying he thought I was fiddling the bookies. I wouldn’t even know where to start. We definitely weren’t doing that."
It is not surprising that Benita has been underestimated. She only decided to stand for London's mayor last October.
"I’d been thinking about leaving the civil service for several months before.
"People were saying, 'You’re doing what? You’re going to go and run for what?' It’s not that illogical.
"I thought, 'Actually do you know what? The mayor was setup to be about an individual leader for London.' The whole disillusionment with party politics was already happening.
"I had done the calculation around when you have to start the campaign. I went into the office in October, wrote my resignation letter and handed it in."
Benita spent 15 years in Whitehall, and was working as a civil servant at the Department of Health when she decided to stand.
"I was against the NHS reforms from the start because there was no democratic remit," she says.
"They were never in the manifesto and actually Cameron stood up and said that we are not going to do a top-down review of the NHS.
"I was there when Lansley came in with the fully-formed plans so I know that this was complete rubbish and that this was always on the books. I didn’t like that…
"I just think it was flawed on so many levels.
"It’s so expensive, so unjustified in terms of what the benefits.
"It was definitely the last straw for me."
She gained one big civil service backer from her time in Whitehall – former cabinet secretary Sir Gus O'Donnell (now Lord O’Donnell of Clapham).
The man who was known to other civil servants as 'GOD' because of his initials has been a force in her fight for mayor.
She calls him 'Gus'. What's the best piece of advice she's had on standing for mayor? "Enjoy it. That was from Gus."
Later in the day, he texts her about one of the other candidates.
"Having Gus backing me is a big help," she adds.
Other public figures have also voiced their support. "The other independent candidates who have stood, like Martin Bell, at least had recognition," Benita says.
"I didn’t have any name recognition.
"Peter Jones from Dragon’s Den did a social media day for me. He told everyone to follow me on Twitter."
Other names who have expressed their support include Tom Conti, Martin Bell, Janet Street-Porter and Michael Portillo.
She also credits social media for much of her campaign's success thus far. "I'd never twittered or tweeted before January," Benita admits.
"We’ve got a very good website up and running, a good Facebook page. These things don’t cost a lot of money. We don’t have a lot of money but they have given us a big reach."
Because she is not a member of a political party, Benita will not be granted a party election broadcast, or invited to take part in many mayoral hustings.
"It is anti-democratic," she says, raising her voice for the first time. "[The BBC guidelines] are out of date." But she doesn't seem that surprised that the broadcaster ruled against her.
Indeed, she doesn't even have an election broadcast ready. "We can do one very quickly," she says. "We’ve got people lined up to do one. I’m not going to do a gimmicky one. If I get one, I’ll do a very straight piece to the camera."
Rumours have spread that Benita is aligned with Labour politics and could split the Ken Livingstone vote.
Benita rolls her eyes when this is put to her. "If people listen to what I’m saying, I don’t want to be a party politician," she states.
"I want to be independent. I said I voted Labour in the past but I had some really hard commercial policies in there as well, like the Heathrow decision.
"I don’t think party politics means the same to people of the generations below me now," she saus.
"There is no Labour Party. What are they at the moment? If I was going to be a successor to Ken, I wouldn’t know what that was. I think Labour is in complete meltdown."
There has been a backlash to not having a party machine behind her though.
"There have been all sorts of accusations about who I’m being funded by," Benita says.
"I think UKIP started the rumour I was being funded by the Blair Foundation and someone else came out and said, 'No, she’s on David Cameron’s payroll.'
"And then I think it was Harry Cole who said, 'It’s Virgin! She’s being funded by Richard Branson.'
"I’m not being funded by any of those. I don’t have any corporate sponsorship."
So how is she paying for her campaign then? How is she funded?
"I’ve got lots of little donations from lots of people," she says.
"The biggest donation was £2,000."
She stops herself. "Actually no, I think I got one yesterday for was £3,000.
"I can’t wait to publish my funding because there are so many rumours going round about who is funding me.
"People are going to look silly when they see my funding. There is no big corporate in there."
She pauses, then adds: "If one suddenly comes forward now, I’m happy to take their money. Or if somebody offers me loads of money, great!
"But it’s lots of modest donations from people."
It's perhaps hard to see why large businesses would provide Benita with financial backing. She has no hope of winning.
But she has made an impression. So what is she going to do after the mayoral contest to capitalise on her new status?
Benita won't be drawn. "I'm honestly focused on 3 May,
"I don’t want to get distracted by thinking about what else... Lots of opportunities… Lots people have suggested different things during the election campaign...
"I don’t know, it’s all good, whatever happens."
In Acton High School, a gaggle of school kids quiz the only independent in the campaign for London mayor. They are all under 18 – too young to vote. But Benita still spends an hour answering their questions.
In fact, education – over which the London mayor has very little power – forms a key plank of Benita's manifesto.
She recently told Mumsnet: "Unlike the other candidates, I have produced an education and youth manifesto because I want every child in London to have the best possible opportunities.
"The way in which we educate our children isn't working. London needs 167 new primary schools by 2015, just to meet the current projected shortfall of some 70,000 places."
She turns to me: "The strategy that I’ve got does not require legislative powers.
"The lobbying government for primary schools is a lobbying job. I won’t apologise for that in the same way that Ken and Boris will say that they are going to lobby for Crossrail."
The session with the kids draws to an end.
One shy girl sidles up to Benita.
Her two friends nudge encouragement.
"Um, I was just wondering where you got your shoes from?" she asks.
"Oh, these," says Benita, looking down. "They're from Banana Republic."
The girls nod in approval and push each other out the door.
Benita smiles and absent-mindedly clicks her heels together.
Our politicians may not be ready to ditch the sensible shoes quite yet.
But Siobhan Benita is certainly making a dent in this mayoral campaign.