The Chancellor will tack right to unsettle Cameron: this is a good time to buy Browns

One day at the Commons recently, just before Prime Minister’s Questions, David Cameron found himself in the gents next to Gordon Brown. The two said a brief hello and then silence fell. As Mr Brown left, he said to the Conservative leader over his shoulder: ‘Good luck’.

What struck me — beyond the mischievous interpretation that this was a shade disloyal to his own leader — was that it was the first time Mr Brown has sent a message to the Tory leader that their relationship will outlive the premiership of Mr Blair. Unless a meteor arrives to unseat him from the role as successor to Mr Blair, Brown vs Cameron is the shape of the next election. Indeed, its first skirmishes are already being fought, even while the PM remains stubbornly in post.

The Times/Populus poll this week shows that voters too are beginning to consider the prospect. While the ‘Blair brand’ gets a pasting, asking respondents about a Labour party led by Mr Brown produces a two-point rise for Labour and a better share of the Lib Dem vote.