Election 2015: No TV debate game-changer? Well, perhaps one

There was no game-changer. No single "moment", no zinger, no gaffe which looks set to re-shape the course of this election. Save perhaps for one.

That was the presence on the stage of not two or three party leaders but seven - a debate in which the talk of a new sort of politics, multi-party politics, became visible reality.

If that gives a boost for UKIP's Nigel Farage with his laser focus on immigration and his attack on the "Westminster parties" - as the early instant polls suggest - it will worry the Tories.

If it also promotes Natalie Bennett's Greens, Nicola Sturgeon's SNP and Leanne Wood's Plaid Cymru after their assault on austerity - it will frighten Labour. The consequence could be an outcome more unpredictable and more uncertain than any election for years.

The leaders of the three main parties arrived with a clear purpose which each will, I suspect, feel they achieved.

'Battle over soundbites'

David Cameron stressed the need for stability, security and continuity and repeatedly warned about returning to the past. He arrived with a huge personal advantage and will be relieved that he made no mistake that will have dented that.

Ed Miliband made the case for change, a focus on the future - not the past - while trying to reassure viewers that "if I was your prime minister" the country would be safe. Once again he will have defied the pitifully low expectations that many have had of him and is sure to get a boost.

Nick Clegg again and again argued the need for balance with the presence of the Liberal Democrats as a guarantee. It was a reminder of the debating power he displayed five years ago but will it be enough to cut through the public anger he's attracted since joining the coalition?

Remember, though, that few will have sat throughout the whole two hours of this debate. Indeed, a minority of voters will not have watched at all. So, many people's views of who won will be shaped by the instant polls - even though, as I blogged earlier, many of those polled have long ago made up their minds - and the battle over which soundbites will be replayed tomorrow and over the next few days. My hunch is that battle is most likely to be won by Sturgeon, Farage and Miliband.

This debate does not look likely to have determined who will win the general election but it may crystallise one single, simple and hugely significant fact - the shape of British politics has changed for good.