There's considerable confusion among Tories at the moment around the Alternative Vote (AV), and it's not simply due to the party's lacklustre campaigning effort against electoral change, but because some sincerely think Cameron wants the No vote to win. He doesn't. Indeed, for the PM, nothing could be worse, as it will finally bring him and his supporters inside the party up against the reality that they lost the 2010 general election.

The next election, which a No victory will bring substantially closer, is a grim prospect for the Cameroons. Not least because the Tories won't have Gordon Brown around to do Labour's election-losing work for work for them. Every inaction and mis-step by the supposed Tory "No" effort is still further proof of Cameron's desire to see "Yes" win.

Why will the "No" vote be so disastrous for Cameron? Because it will tear out the heart of the Liberal Democrats. For Labour, watching socialism die over decades was one thing, but for the Lib Dems, the defeat of their holy mission, electoral change, on one brutal night cannot happen without it costing Nick Clegg his job – his party will demand a Lenten sacrifice.

Furthermore, it can't happen without the Lib Dems realising that the next election will be fought on first-past-the-post, with their party stapled to Cameron and George Osborne's record. What worth a coupon election when you're tied to a brand as contaminated as that? It won't be considered, and Clegg's successor will seek a way out of the coalition at the first available moment.

It's the lesson every other coalition overseas teaches us: the smaller party prudently looks for its way out. The next election will happen well before 2015.

For all that, the main "No" campaign has been utterly unengaging. Are the polls that show an AV "Yes" lead convincing? More so, for example, than the 2:1 lead "No" had to Common Market membership at the start of the country's previous national referendum, in 1975?

Some Tories muttered that it wasn't a good sign when Matthew Elliott left the Taxpayers' Alliance to head what's currently the largest "No" campaign grouping. The scepticism was rooted in the TA's tendency too often to produce gimmicky press releases rather than hard research, and the fear that their opposition-era unwillingness to criticise Osborne's distinctly un-TAish Treasury team too loudly bore an inverse relationship to the expectations TA staffers harboured of post-election SPADships. In other words, for many on the right, this "No" campaign has always had a tame air to it.

The hard-right sneering at Elliott is doubtless all very unfair when not just downright bitter, but there's still something wrong with the No campaign beyond merely its present unimpressive tactics. It ought to have been Labour-led. Defeating AV is something Labour should have a vested interest in, and most Labour MPs see that. Yet the No campaign is Tory-dominated. Whether Ed Miliband's eccentric preference for AV has held back ambitious Labour flacks from getting involved, or it's been something to do with the culture of No2AV itself, is irrelevant. With Cameron clearly equivocal about stopping AV, as much Labour support as possible should have been sought. Margaret Beckett on a letterhead just doesn't cut it.

At the moment there aren't any "official", Electoral Commission-designated "Yes" and "No" campaigns, just one main, prominent organisation on each side. Should the AV referendum end up being delayed by the Lords, it wouldn't surprise me if a rather more vigorous "No" campaign emerged. However, that's just speculation; what's not is that David Cameron has been even more limp than normal in defence of his alleged beliefs.

A cynic might say that, given his electoral track record, that the best thing Cameron could do to secure a "Yes" vote would be to put himself at the head of the "No" campaign. But that would take courage, and he has never shown any of that. This Tory leader will offer Majoresque delay, evasion and short-term expedients, but whether that will get him the "Yes" to AV vote he so desperately needs is very uncertain indeed.

The bill for losing the 2010 election comes ever closer to being paid by the man who lost it.