Paul Sykes has everything. The mansion, the maid, the Jaguar. His home on the Studley Park Estate with its drive running right up to Fountains Abbey is, in all honesty, the most beautiful I've ever been in. But he's still seeking something more.

Not money. He's lost interest in that - £650m is enough for anyone. It's politics and philosophy that really absorb him now.

He's been bankrolling UKIP ever since its birth, spending millions to get it to this point. Once a Tory, he left the Conservatives in 1992, determined that Britain should never join the Euro. Already a multi-millionaire through his scrap metal, property and internet businesses, he funded eurosceptic Tory candidates at first, before joining forces with Nigel Farage.

But Paul Sykes is about to turn the tap off. "It's like holding the back seat of a cycle, there's a time when you're to let go", he tells me. That time is the next general election, when Mr Sykes hopes UKIP's swelling membership will bring in enough funds: "It's getting to the stage where I'm hopeful they'll still need me for little things, but the funding job's going away."

But until then, there's an election to be fought, and Paul Sykes is in charge of the party's marginal constituencies. He tells me they'll now target at least 45 seats, given the result in Rochester and Strood. And it's Labour voters he's setting his sights on.

Sykes still considers himself working class (his father was a miner) and he complains about immigrants undercutting wages and taking low-paid jobs. "The unfairness is that we've had borders removed and who's suffered from that? Certainly not big business. Big business loves wage compression; loves wage competition. To bring someone into the country on a sixth of the wages, they [British workers] can't compete with that."

Interesting when Mr Sykes himself was once in 'big business'. I ask him if it's a bit hypocritical to knock immigration, when he can't promise he hasn't employed immigrants himself, and even admits he'd be tempted to in future: "Of course I would. I'd employ anybody. But you've got to start taking responsibility for people who haven't got work, who are low paid...you've got open borders where people are coming in that are not just competition, they're wiping these people out, they can't compete."

I joke that UKIP sounds more Labour than Labour itself. But Paul Sykes doesn't like being compared to Ed Miliband. "I think he's like a student...a geeky historian. I couldn't see him in a job", he says of the Labour leader. As for a coalition between the two parties, definitely not. "There's no way. We've got to look at what the outcome is [but] just mentioning Labour and thinking about Ed Miliband, I couldn't possibly", he laughs.

Besides, Paul Sykes might not be so interested in coalition deals in 2015. He's got his heart set on a far bigger question. His lounge is full of books about the Earth and how to save it - surprising when UKIP are sceptical about climate change. "I'm going to be there when they stop the last tree being cut down", he says. In fact, he's planted a million trees on his estate, and is now heavily involved in environmental projects across the globe.

I'm not sure Paul Sykes will ever 'retire'. But he does seem ready for a new and more spiritual journey. He's launched companies, built shopping centres and helped create the biggest force in British politics this millennium. But next, Paul Sykes wants to save the world.

Video: ITV News