The TV debates that will change all future election campaigns

Who’d have thought it? A Presidential-style debate in the UK.

It is expected to convulse the election campaign. That’s why the parties wanted to sort out the principle and the dates so early.

It gives the Liberal Democrats one hell of a leg-up, and that’s high in Labour’s calculations (they want the Lib Dems to do well against the Tories to limit Tory gains) but not as high as the fundamental point: Labour strategists think Gordon Brown might just make David Cameron look naive, not versed in the ways of the world and not a man to hold the tiller in dangerous times.

Most opposition parties would be euphoric about the prospect of equal status debates with an incumbent (and the Lib Dems are ecstatic) but you get a whiff of nervousness about the Tory camp.

It’s not panic – they asked for this and want it. Deep in their hearts they believe it’ll work for them. But David Cameron has more to lose from this debate and his people know this.

So far the agreement is for three debates in the election pending period – ITV first, then Sky, then the BBC.

Alastair Stewart, Adam Boulton and David Dimbleby are the agreed questioners, the parties did not want random questions coming from the public though there will be voters present in the audiences.

Labour wanted more debates starting earlier. So far, that’s not in the agreement. But Labour clearly feels it is worthwhile losing some of its opening demands to get the agreement.

Labour’s judgement could be very flawed but right now it is that the constitutional innovation unfolding before us tonight will help to tighten the gap between the two main parties.

As for other parties, the SNP for one told me tonight they were considering legal action to stop the current plan.