How Cameron could neuter UKIP and win the general election

Obviously the fact that Britain has decided it's time to go out bombing again is the bigger news story, but the defection of Mark Reckless to UKIP is still a major problem for David Cameron. It's really not a good look when your own MPs decide to abandon you, particularly on the eve of your conference.

On the other hand, it being the eve of conference means that Cameron has the opportunity next week to make a grand statement against UKIP in an attempt to stop the rot (in all senses).

But there's no point in imagining that dog-whistles on immigration and multiculturalism will be sufficient. That's territory that UKIP are always going to claim as their own. Instead, the real weak link in UKIP's armour is, oddly enough, Europe itself. Most people don't care much about the issue, but some do, they care very much indeed and - from a Conservative perspective - they're a worryingly significant minority. Cameron's offer of a referendum gained him a little time, but by now the UKIP response has clawed back some of the initiative; you can't trust his promises, goes the argument, look at the betrayal over the Lisbon Treaty.

So Cameron should take the opportunity at conference to do the one thing that only he, and not Nigel Farage, can do: announce the exact date on which the referendum will be held.

He's already said that it'll be before the end of 2017, but that's still too vague. There is a round of local elections due on Thursday 4 May 2017. That'd be a good date to choose.

Announce now that, in the event of a Tory, or Tory-led, government, an In/Out referendum will be held on that specific date, and suddenly the airy promise becomes concrete reality. He'd seize the initiative entirely. Every front-page would have a graphic of a calendar showing 4 May 2017. Eurosceptic commentators and Tory backbenchers would be delighted; Europhiles would reluctantly have to accept the concept of democracy.

It would leave Cameron no wriggle-room, of course, but the reality is that he can't afford the luxury of wriggle-room anymore; the UKIP threat is too great. He needs to squash comprehensively the impression that somehow he'll twist and turn and renege on his promise.

For those Tory voters tempted to desert because of Europe, there would no longer be any incentive to their votes elsewhere. Farage isn't, and never will be, able to match such a pledge. As long as it's credible, it would trump any card UKIP can possibly play. Which would leave UKIP to carry on making inroads into the Labour vote, where its appeal isn't rooted in the European issue in the first place.

Obviously there will still be disgruntled Tories, but their real bone of contention is with having a pro-European leader in the first place. And if they want to change that, they need to mount a more efficient challenge. Which they would undoubtedly lose, because there is no plausible Eurosceptic alternative to Cameron, and they've already tried - with Iain Duncan Smith - having an implausible one. Much good that did them.

I'm also fairly certain that in such a referendum, Britain would vote to remain in the EU. And since that's the result the EU would want, it will swiftly get over its cries of outrage and start working to ensure that some concessions - however cosmetic - are made in order to strengthen Cameron's hand.

In the (unlikely) event that Cameron does not emerge from the general election as prime minister, the referendum presumably wouldn't happen. And that in itself would be a nice legacy for Cameron's successor. S/he can still make a big deal of 4 May 2017, using it as a rallying-point against Ed Miliband's by-then beleaguered government. The Day That Democracy Forgot would make a nice slogan.

It'd be a big step for Cameron, who isn't a notably adventurous politician. But things are getting tight and it's time for a bold move. Played right - with sufficient statesmanlike gravitas - it could be decisive. It would lose him no support whatsoever and would bring sufficient numbers of disaffected Tory votes back into the fold to ensure victory in the general election.