David Cameron's end game. Why now?

With the election coverage now well and truly in full swing, David Cameron wrong-footed the hack pack this evening with an interview with the BBC that raises the question of his departure at the end of the next parliament. He says terms of office are like Shredded Wheat - two are 'wonderful', while three are too many.

It's a great bit of product placement for Shredded Wheat - and probably cheaper than wheeling out Ian Botham again. It also got me wondering what other breakfast items can be compared to terms of office. Ed Miliband's buggered if his are like bacon sarnies - struggling to manage one.

Still, on a serious note, commentators have rushed to debate whether the PM was right to be so loose lipped in his kitchen (is the the kitchen election??) or whether he should've side-stepped a discussion his own future since barely anyone was debating that anyway.

The suggestion goes that Cameron, having raised his own departure, risks making himself a lame duck (that pillock from Sleaford would claim his house on expenses, presumably) and opens up a leadership debate that they could do without during an election campaign.

As a pretty slick PR man I doubt the PM was wrong-footed. Certainly not in a cosy kitchen interview. He too shrewd for that. So, assuming he meant to say it, why now? Aren't the commentators right? Doesn't this threaten to disrupt his whole campaign?

Here's why I reckon he took the plunge:

*From the very start, the Conservatives have been keen to make this election a question of leadership. The TV debates have blurred this issue a little bit, making Cameron look scared to take on Miliband in a head-to-head challenge, a decision calculated so not to let his rival get exposure. I think, in part, he wanted to get back the leadership agenda and what better way to do so than by making the story about himself? Seem daft? Well, don't forget that Cameron polls as well if not better than most of his rivals when it comes to approval ratings. If we're all focusing on the leaders as personalities, the Tories think they're in safe electoral territory.

*By openly mentioning three possible successors he's probably also trying to show that the Tories have 'bigger beasts' waiting in the wings than Labour has on its front line. The likes of Theresa May, George Osborne and, in particular, Boris Johnson will be much more well-known to the wider public than Labour's front bench. It's all part of the 'long term plan' and 'safe pair of hands' message.

*He's also potentially dampening the enthusiasm of any potential plotters and openly discussing what everyone has known for a long time - that Boris is being lined up for a tilt at the top job after he walks into a safe seat. There's no need for any furtive talk on that score any more - and the potential for BoJo to attract a headline for doing something divisive may have been diluted too.

*By starting to talk about a third term, he's getting it in voters' heads that he could be around for another five years, getting them to consider him to be Prime Ministerial and looking beyond this election. possibly also deflecting short term embarrasment over the TV debates or the Afzal Amin story. It might also be a way of telling more hardline members of the party that he wont 'go on and on'.

I know it's not a foolproof case, but it maybe goes some way to explaining why Cameron spoke so openly about his future. Of course, the questions don't stop there. What if he doesn't win an outright majority? Will that, presumably, be the end of him in frontline politics since he doesn't wish to fight for another term in 2020? Does he favour any of that trio in particular? Would he not have to go if he lost the EU referendum anyway? These are questions, of course, that keep the spotlight firmly on him and the Tories and less on Labour and his rivals. It was once said of the Blair/Brown era that the talk of their rivalry was tolerated because it meant no-one was focussed on the Tories.

It's odd that, when it comes to politics, we spend so long asking politicians questions and hammering them for not answering and yet when they do we spend ages debating whether or not it was the right move to answer the question in the first place. I guess that's largely because why someone says something is probably as important as what they've said. This was certainly a headline grabbing move by Cameron - but maybe that was his intention after all.

On Thursday he's away from the cozy kitchen and into Jeremy Paxman's bear pit. It'll be interesting to see what he says there...