Here's a revealing snippet from Ben Brogan's Telegraph column  this morning, which suggests that David Cameron's days will be numbered if he loses the election.
If the Tory leader is not prime minister on or soon after May 7, the parliamentary party will turn on its leader. Already the 92 Group, a club of Thatcherite MPs, is planning a meeting in the week after the election that could demand Mr Osborne's head. A coalition of the excluded, the irreconcilables, and those nursing grievances over the handling of the expenses inquiry is preparing to break its silence. Up to 20 MPs are said to be ready to speak out.
It is with this possibility in mind that Cameron has previously ordered the party's powerful backbench 1922 Committee to change their rules to make it harder to remove a sitting leader. Under the current rules, a leadership contest is triggered when 15 per cent of the party's MPs submit a request for one. Once lodged, a request cannot be rescinded, so the number can gradually rise over a period of weeks.
But Cameron is expected to change this rule by putting an "expiry date" on letters. Rebel MPs would have to write again after a certain period.
Either way, it is hard to imagine the party's backbenchers tolerating a further period in opposition under Cameron. Many are unreconstructed Thatcherites who only accepted the 'modernisation' of their party in the belief that Dave was a winner.
If this assumption turns out to be wrong, we can expect the Tories, as usual, to act with Darwinian ruthlessness in removing their leader.