Armchair election: Vote Clegg, ditch Brown – now that’s a strategy.

Nick Clegg has a problem but it’s a nice kind of problem. The Lib Dem leader is enjoying a remarkable poll surge which he needs to defend and enhance. He is unlikely to be troubled by most of the attacks other parties are likely to launch on him, which will seem only to prove his point that the other two are just the two old relics defending the status quo.

But one attack does cause him difficulties and it is no surprise therefore that the Tories are pressing it hard. The “Vote Clegg, Get Brown” line is effective for two reasons. The first is that it could shore up wavering Conservatives and the second is that if it takes root it can undermine the Lib Dem claim to be the true party of change. As I wrote yesterday, the change mantle is the one David Cameron needs to reclaim if he is to win and it is the one he foolishly ceded to Nick Clegg in the debate. The claim that a Lib Dem surge could sustain Mr Brown unless the Labour vote collapses entirely has the added advantage of being true.

Mr Clegg is already aware of the dangers of a Brown bear-hug, but there is a way out of this dilemma. He could make clear that the Lib Dems will not sustain a defeated prime minister should they hold the balance of power. This is not to say they would not side with Labour but that they would insist on a new leader as the price of doing so. Mr Brown is already unelected. Were he to lose his majority he would be an unelected prime minister, rejected by the voters. There is no reason why Mr Clegg could not insist on a change of leadership as the price of Lib Dem support.

Of course at the moment Mr Clegg doesn’t want to talk about anything other than winning and until and unless his poll surge recedes one cannot blame him. But this gambit would be a way to rebut the “Vote Clegg, Get Brown” attack and remain the face of change since he would be guaranteeing something different whatever happens. An added advantage is the panic it would sew in the ranks of Labour strategists as it would split the Brown camp from the coalition camp.