There is one fear that is keeping Cameron awake at night, that Gordon steps down in a civilised way. Either Gordon hanging on or a vicious civil war in the Labour Partyare the two options he needs. But if G Brown Esq packed his bags, citing a heart mumour or whatever, and Postman Pat took the reins by acclamation than he would be worried.
Could it really happen? Personally, I'm not so sure. The formal procedure required for the Labour Party to remove a sitting leader makes a coup unlikely, so Gordon Brown would have to step down voluntarily – which I can't imagine. Having wanted to be PM for so long, he'll prefer to cling on as long as possible.
More to the point – would anyone else really want the job at this stage? Ambitious politicians will want to wait until after the next election, rather than take over a sinking ship and captain it to a landslide defeat (a sure-fire way to end a career in Westminster). Any new leader would probably be forced into calling an early general election – the public would not take kindly to having a second unelected prime minister imposed on them in a single parliament – and would have almost no opportunity to turn things around.
I may be wrong, but I think we’re going to have to put up with Gordon Brown for a little while yet.