So will he jump? The fever gripping Labour’s conference as Gordon Brown took to the podium on Monday answered with a resounding Yes. There was scarcely a soul in Bournemouth who did not believe that this, Mr Brown’s conference debut as UK prime minister, would be his last before a general election.

In that broad judgment they are probably right. Mr Brown pitched to the nation’s electorate as much as to enthusiasts in the hall. He may once have called himself a socialist. Now he speaks for a “Britain of aspiration and a Britain of mutual obligation”. Every constituency, Conservative as much as Labour – firefighters, soldiers, farmers, teachers, health workers – heard that the prime minister was on their side. A week or so ago Mr Brown was giving Margaret Thatcher tea in 10 Downing Street. On Monday he ostentatiously eschewed the ritual abuse hurled on these occasions at political opponents. David Cameron, the Conservative leader, was not even mentioned. Mr Brown, an ally explained, saw no reason to offend Tory voters. The big tent stretches ever further.