If Vince Cable was once a plausible caretaker leader for the Lib Dems, he isn't any longer. The revelation from his old friend Lord Oakeshott that he was aware of polling he commissioned showing that Nick Clegg would lose his seat (a fact he did not disclose in his condemnation of the peer last night) has left him looking duplicitous and treacherous.
Clegg will now almost certainly lead the party into the general election for the reasons I outlined this morning: there is no Heseltine-style figure prepared to challenge his leadership; he has the backing of a majority of Lib Dem MPs; most of the party's current and 2010 supporters want him to stay (the Lib Dems' key target group); and it is far from certain that the gains from deposing Clegg would outweigh the costs.
But when a leadership contest is held it is clearer than ever that the most likely victor is Tim Farron. The party president is now the only senior figure to have been untainted by the coalition (having not served as minister) and by allegations of plotting. Through his energetic campaigning and social media presence (few politicians reply to more tweets), he has become the darling of party activists and topped a Liberal Democrat Voice leadership poll today. Unbound by collective responsibility, he has been free to vote against tuition fees, the NHS bill, the bedroom tax and Secret Courts. If Labour is the largest party after the next election, and Clegg is forced to stand aside, Farron will be the ideal man to lead the party in a progressive coalition.
He is also one of the few Lib Dems who can be certain of re-election in 2015 (unlike his principal rival Danny Alexander). He has a majority of 12,264 in his constituency of Westmorland and Lonsdale (increased from just 267 in 2005 through relentless campaigning) and the party finished first in South Lakeland in the European elections (the only area in which it did so). After the waning of Cable's star, Farron is the man to watch.