Is Liz Truss toast?

Less than a month since she became Prime Minister and already the question is: "How long can Truss survive?"

The chances of her being ousted before the year end are now up to 13% with Smarkets; if that came to pass she'd be the shortest serving PM in history. The rules of the backbench 1922 committee currently do not allow for a leadership challenge within a year of a new leader being appointed although that may be fairly meaningless given that they can change their rules at any time. 

It took 60 days between Boris Johnson announcing his resignation and Truss being installed as the new leader, with most of that being the seemingly never-ending rounds of members' hustings once the MPs had narrowed it down to the final two. The party could easily cut that down, so it's perfectly possible for a new PM to be installed before the year end if Truss did lose a no-confidence vote in the next few weeks.

The other possibility is that MPs manage to arrive at a consensus candidate thus negating the need for the members' vote. That's what happened in 2005 when the Tories (in opposition) passed a vote of no confidence in Iain Duncan Smith. The party quickly coalesced around Michael Howard, the likes of Ken Clarke decided not to mount a challenge and Howard was installed as leader eight days later.

Could Sunak be installed at Number 10?

In the "coronation" scenario, one person immediately stands out as the most likely candidate: Rishi Sunak. He was the preferred choice of a plurality of MPs following Boris Johnsons' resignation and the events of the last week seem to have vindicated much of his pitch during the leadership campaign. If the aim is to install a face that the markets trust to run the economy, Sunak seems like the obvious choice. 

This scenario does require dissuading anyone else from running for the leadership. Would Boris Johnson fancy his chances? Maybe, but I'm assuming that Tory MPs will consider him a very risky gamble in the current crisis. I would be surprised if any of the defeated candidates from the summer's leadership contest though they had much of a shot against a Sunak bid which might be able to demonstrate overwhelming support almost immediately. Sunak to be PM on 1st January seems like a reasonable bet at the current 27.0.