This could be an opportunity for him. Clear out the government, go with a handful of ministries and a very small government (say no more than 20-30), and then stare the Tories down by saying that he's setting a new course of government without useless career politicians. If he packed the government with people from outside Westminster, he could sail the "People's PM" ship and give himself a chance at survival.
It would be a high risk strategy, but he would effectively be telling the Tories that he'll run against them in the next election, which would do huge amounts of damage and ensure that they wouldn't win. With his defiant behaviour so far, it could just motivate enough of them to keep him around for fear of what happens next.
It's a far-fetched scenario and unlikely to happen, but then again, I thought earlier that he would be resigning by 10pm!