The last time that Nigel Farage visited a lap-dancing club was “during the last French presidential election campaign, with one of the candidates”. When he told us this we were not sure, for a moment, whether he was joking.

It turned out that he was not, it was just a typically candid and recklessly off-message remark, which may not do much for Anglo-French relations either. But, like the UK Independence Party that Mr Farage leads, it can be quite hard to tell whether he is serious or not.

This is the question that mainstream British politicians — David Cameron in particular — have to answer too. Is Mr Farage the threat to Mr Cameron that he would have us believe, or is he just a leader made to look good by a rag-tag bunch of eccentrics? Is UKIP finished now that the Europe issue has faded, or is the bland sameyness of what now passes for national debate among the main political parties its greatest opportunity?

Certainly, UKIP recently picked up two Conservative-minded peers, but it still has a talent for squandering its success. The 12 MEPs whom it won largely as a result of a publicity boost from the neon-skinned daytime TV host Robert Kilroy-Silk have dwindled to nine: Mr Kilroy-Silk split from the party acrimoniously (two others went under a cloud). The party is also facing a court battle with the Electoral Commission that could easily bankrupt it.

Mr Farage’s reaction to all this? He is never happier than when casting himself and his party as the plucky David to the state (and status quo) Goliath.

“I think you can’t put a cigarette paper between Labour and the Conservatives on most of the big issues,” he said. “So the Tories are obsessively worried about us because of this drift towards us. They think we could cost them the next election.”

If Mr Farage hopes to appeal to disillusioned Tories, he makes a good decoy duck. He was a Tory, briefly, when he was a stockbroker in the early 1980s, having decided to “go out and make money”, and anyone nostalgic for that era will find their man here. He has the kind of flash charisma often found on the right: a rogue’s charm, an impeccable suit, a trilby hat over a fierce side-parting and the almost obligatory minor sex scandal to boot. But more of the hanky spanky with Liga the 25-year-old Latvian later.

This, along with an admiration for Baroness Thatcher’s legacy, makes him attractive to the kind of people that we used to think of as typical Conservatives: even stalwarts such as the free-market economist Tim Congdon, or activists such as William Hague’s former constituency chairman, have defected. He claims, a little improbably, that some members of the Conservative front bench, in the Commons as well as the Lords, have confided to him that they actually voted UKIP at the European elections.

“There is this split within the parliamentary party, but the real split — and this is what they are terrified of and they damn well should be terrified of — the real split is between the official party position and what their own membership think.

“And this is very interesting. The Tory branches, the local council candidates, the real workers in the party — impossible to give you a percentage, but if I said to you that 80 per cent of them would agree with UKIP I don’t think I’d be far wrong. This is a real problem for them.”

The election of David Cameron, who dismissed UKIP members as “fruitcakes, loonies and closet racists”, has left the field clear for Mr Farage on the Right (well, for him and the British National Party). Unsurprisingly, he has strong views on the Conservative leader.

“I liked him because he’s a smoker, you see, which is a very good thing,” Mr Farage said first. (This may have given Mr Cameron added incentive to give up). “He’s a very likeable bloke. Pleasant. But he doesn’t actually believe in anything. I don’t think he believes in anything. Is he in politics because he’s got some great driving, burning ambition, because he believes in something? No, of course he doesn’t. It’s about rank and becoming prime minister. Which if we were an independent country would matter enormously.”

The Tory high command is so afraid of him, Mr Farage insists, that there is “a very concerted attempt to have a go at us. It hasn't happened before, that’s the point. The tactic before with UKIP — from the Conservatives particularly — was just to ignore them.”

He thinks that Conservative Central Office is targeting him, and cites an effort by Tory MPs around the country recently to publicise the case of a man who claimed that he had been dumped as a UKIP candidate for a winnable local election seat when the party found out that he was disabled. “They’ve decided to turn very nasty.”

This doesn’t sound more than normal political battle tactics, we suggested. “Well to me, perhaps I’m naive, but to me the disabled thing was pretty nasty . . . Maybe this is part of the growing-up process for us. It’s an unusual time now. Maybe this is part of us having to grow up and that it is difficult going.”

He insisted that the story “simply isn’t true”, yet ten days ago Mr Farage was quoted as saying: “He could not be a mainline candidate if he physically could not do the job. I could run down the street but I couldn’t make an Olympic athlete.”

For a man with the appearance of plain-speaking it can be quite hard to get to the bottom of things. (Reminding us, for instance, of Liga the Latvian. But more of that, as we said, later).

Mr Farage has been highly effective in Strasbourg, blowing the whistle on several cases of corruption that became Europe-wide scandals. But now the threat of the euro or the EU constitution lies dormant, he has riskily decided to focus more on domestic politics, where UKIP has long fared badly. His political inspiration is from Thatcher — not, he insists, the Tories.

“Thatcher was not an old-fashioned Tory — she was an aberration. I think the more I read about the history of the Tory party or politics, you realise that Thatcher actually wasn’t Conservative at all, she was a radical economic liberal.”

And that is how he would describe himself: “Absolutely. I don’t think I’m a Conservative at all.”

A work in progress, their manifesto so far includes the “unashamed” return of grammar schools, less progressive taxes, and strict border controls to stem the tide of Eastern Europeans.

“Let’s have a work-permit system. Absolutely fine. Got no problem with that. But not complete open rights of settlement, plus your extended family if you wish. I mean I know this is an area that a lot of people don’t like talking about. But I think we are right on this.”

He said that, since he took over six months ago, he had purged his unruly party of anyone veering towards the BNP or any kind of racist agenda, leaving it politically united, “and if we’ve got one or two eccentrics who wear hats, I mean so what?”.

More immediately, he faces the prospect of going bankrupt: the Electoral Commission is taking UKIP to court over its refusal to pay to the Treasury £367,697 received from Alan Bown, a British bookmaker, because he wasn’t technically on the electoral register at the time.

Mr Farage can hardly wait: “I’m looking forward to it. I think the contrast of the State, the bureaucrats, the weasels, on the one hand and honest Alan on the other is going to be wonderful. And I do actually think that we still have a great sense in this country of fair play, of giving the underdog a chance. And this is clearly some form of victimisation.”

The members of the Electoral Commission (does it remind him of the European Commission?) are “the most utterly useless group of people: just appalling people, disgraceful people, horrid people”. They had let the Liberal Democrats keep £2.4 million from a man based abroad who was now in prison, they were silent on Labour’s cash-for-honours affair, but he said that they had thrown the book at UKIP over what was a small administrative error.

Politics is personal for Mr Farage. If Mr Cameron has to have a wind turbine on his roof and bicycle outside his front door, Mr Farage indulges as many vices as he can as an “Up yours, Delors” to the po-faced rule-makers (their quirks, like EU-banned bendy bananas, ironed out).

“I like a pint after work,” is the way he puts it, but as anyone who knows him will tell you, that is putting it mildly. He briefly gave up smoking, “but when the Government announced the ban, of course, I started again” (he is not entirely joking). He is as candid about his transgressions as a mainstream politician would be paranoid and secretive.

Well, not quite candid perhaps. For there was this Latvian woman called Liga who kissed and told on Mr Farage to the News of the World a year ago. As the newspaper described the alleged event, his “European UNION” was a marathon night during which he “begged her to get MaaSTRICHT with him”.

For the first time, Mr Farage looked a little embarrassed. “Okay I’ve got to defend myself on that . . . That particular situation happened because I had too much to drink. Just as simple as that. Not clever.”

And, as he had insisted to the News of the World and his wife, he had fallen asleep at her house and she had invented all the rest? “Unbelievable,” he agreed. Mmm.

He squirmed, but to his credit he remained polite, despite our unfair intrusiveness — and he still managed a bit of humour. Where was she now, we asked. Had she gone back to Latvia? “No,” he said with a rueful laugh, “because they can all come and live here now, can’t they?”

But if Mr Cameron were to talk cheerfully about visits to lap-dancing clubs in his past he would not survive in politics. “Perhaps I won’t. I don’t know. Maybe we’re living in such an incredibly, ludicrously, politically correct world that perhaps we all have to visit with that sort of standard package. I hope not.”

Whether Mr Farage is individual or narcissist, visionary or idiot, the Conservative Party must hope that he does not turn out to be a dangerous joke.

The road that led to tanks on David Cameron’s lawn

Born April 3, 1964

Education Dulwich College

Family: Second wife is German. He has four children, aged 1 to 18

Previous career: commodity broker, ran own brokerage business from early 1990s to 2002

Political career: left Tories when John Major signed Maastricht Treaty. Founding member of UKIP in 1993

1999: Elected as MEP

2004: Reelected as MEP for SouthEast England, became leader of the UKIP’s group in Brussels

2005: Clashed with Tony Blair when the Prime Minister gave his last address of British Presidency to European Parliament

2006: Parked an armoured personnel carrier outside the Conservative Party’s spring conference, to signify the party was “parking its tank” on David Cameron’s lawn. Won the UKIP leadership election

Hobbies: keen sea angler and shot, and a supporter of Real Ale. Visits First World War battlefields

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