Dylan Jones: The pollster whose focus groups tipped Cameron as leader

Only 24 hours after chatting amiably with John Reid outside his press lunch at the House of Commons last Thursday, US pollster Frank Luntz was in Drones, asking the waitresses if they had seen the Home Secretary's brain. The Sun had asked its readers that morning if anyone had seen Mr Reid's marbles, and Luntz - perhaps worried that the readers might be unsuccessful - was soliciting the help of three waitresses.

As you'll remember, Luntz is the young Connecticut pollster whose focus groups for the BBC's Newsnight in 2005 unambiguously selected the below-radar David Cameron as the Conservative choice for leader. Luntz has since been courted by Tony Blair, and then, at last year's Labour Party conference, more focus groups proved that Reid was the PM's chosen successor (much to Blair's delight). Three months later, however, and Luntz was soliciting the help of Eastern European waitresses in his search for the Home Secretary's grey matter.

Luntz is now in such demand that he's in London every few months ("I don't seem to be capable of keeping windows free in my diary"), and before an official engagement spent two hours giving me his thoughts on the forthcoming US election. Although there seems to be something of a minor backlash against Barack Obama in the American media right now - coming under fire for a largely policy-free campaign - Luntz thinks that, if the Democratic hot shot keeps posing for photo ops with his pretty wife ("They're like a black John and Jackie"), if he can withstand that cocaine problem (he admitted taking it in his youth), and if he can cope with whatever it is the Clinton gravediggers will dig up about his past, then he's still a strong joint favourite (forget about Osama, it's Obama all the way!). The increasingly aggressive Hillary is still in the frame, of course (until, perhaps, Bill is caught with his trousers down again), though with John Edwards and the 25-1 shot Bill Richardson still in strong contention. Richardson is the Governor of New Mexico, and we look like being in the extraordinary position of having a woman, a Latino and a black man all running for the Democratic nomination.

Luntz poured cold water on my suggestion that former Wisconsin Governor Tommy Thompson might be in the frame for the Republican nomination. His welfare reforms did more to drag people out of poverty than any amount of charity, and he performed miracles in the 12 years he was in charge. "But," said Luntz, with a malicious grin, "have you ever been in a room with him?"

We had just finished gossiping about John McCain's Vietnam flashbacks and were about to start praising David Cameron when he glanced at his watch, looked up in panic and said, without a hint of irony, "Well, I better start looking for John Reid's brain. I think he needs all the help he can get."

Dylan Jones is the editor of GQ