Meet the U.K.'s Prime Minister-in-Waiting

Peter Macdiarmid / Getty Images Politically, British Prime Minister Gordon Brown is a dead man walking. Forty-two-year David Cameron is preparing to lead the Tories into power by giving the stiff party of Thatcher an image makeover.

The online petition, which has been signed by more than 40,000 Britons, is straightforward: “We the undersigned petition the prime minister to resign.” And where do you go to sign this e-petition? Number10.gov.uk —“The Official Site of the Prime Minister’s Office.” It would be hard to find a clearer sign of the sad state of affairs at Downing Street in what now seem destined to be Gordon Brown’s final months in office. It’s as if the insurgents are coming over the walls.

Brown has just gone through what even his close allies acknowledge is the worst week of his premiership. On Wednesday, he lost a key vote in the House of Commons, thanks to defecting MPs from his own Labour Party. The next day, the PM was forced to retreat on another issue to avert another humiliating bashing. The previous week was in some ways even more damaging. Brown attracted widespread ridicule for a cringe-making political mini-speech on YouTube. Then a day later, his chancellor of the Exchequer, Alistair Darling, unveiled a recession-driven budget that was poorly received and, for many, an admission of Labour missteps and overspending since it came to power in 1997.

As a former public-relations executive, Cameron knew how to use language to shape his image and reshape his party’s. The Tories were temporarily rebranded on their Web site as “Cameron's Conservatives,” and Cameron spoke often and at length about a responsibility to protect the environment, “social justice,” and “global poverty.”

Brown, 58, has 13 months before he has to call a general election, and the consensus opinion in London political circles is that, because Labour is running 20 or so percentage points behind the Conservatives in the polls, he will wait as long as he can. But the public, the politicians, and the pundits are way ahead of him: As if counting on Labour’s defeat, all eyes are now on David Cameron, the 42-year-old leader of the Tories.

That’s the good news for Cameron. The bad news is that he’s being judged altogether differently today than he was even a few months ago. This is especially true because, as the new budget made clear, Britain is entering a period of negative and then slow growth, fast-rising unemployment and perhaps some attendant social unrest, and rising public debt accompanied by falling spending.

It’s bad news because despite Cameron’s personal appeal, he hasn’t managed to define what a Conservative government would do in office or what he would be like as leader of his country as opposed to leader of his party. In polls, Cameron often scores higher on personal qualities than on leadership qualities. Accused of placing style over substance, Cameron and his inner circle have responded by producing two dozen policy papers on issues from education to energy.

Still, the shape of a Tory platform for government remains frustratingly vague. For example, the 37-page energy policy, as cleverly named as it is (“Power to the People”), mentions the word “nuclear” once—and then only to specify nuclear power’s current share of electricity generation, not to signal the Tories’ position on nuclear. As a member of Cameron’s shadow cabinet told the commentator Andrew Rawnsley recently, “If you look at our legislative program for the first year, it is a blank piece of paper.”

A degree of blankness makes political sense. Cameron cannot be certain of the state of the country, much less the state of its finances, when and if he takes over. Furthermore, too many specifics can dangerously narrow a politician’s appeal when he’s seeking the widest possible support. “Substance is overrated in election campaigns,” says Daniel Finkelstein, a Times of London editorialist and former Tory strategist.