It would be situation critical for the Coalition. For this reason, I suspect that David Cameron wouldn’t shed any tears if the AV referendum passed.
As I write in the Mail on Sunday, Number 10 has moved to install Rodney Leach, of Business for Sterling and No campaign fame, at the top of the save first past the post campaign. Leach is loyal to Cameron, he worked hard to reassure Euro-sceptics about Cameron and to stop any explosion over Cameron’s acceptance of the Lisbon Treaty. With him on board, Cameron can be confident that the save first past the post campaign won’t be run in a way that threatens the Coalition.
AV can be defeated at the ballot box. But only a campaign that is focused on winning and isn’t spending half its time worrying about what impact its messages would have on the future happiness of the Coalition could deliver this result.
One other thing to look out for is Tories for AV. In the past few weeks, a flurry of people have told me that AV is no longer bad for the Tories; that the Coalition now means the Lib Dems will put Tories down as their second preference and that AV will hurt Labour most. I would expect at least one Tory Cabinet member to declare for AV before the referendum.