Those most likely to vote are the old - 78% of the over-65s. Is that because they are dutiful citizens? No, it is because they have deeper affiliations stretching back to the days when parties did stand for identifiably distinct values. Above all, parties stood for different class and economic interests. Them-and-us was spelled out loud and clear: whose side are you on, who stands up for people like us?

There is no united British civic interest, except in matters of national security. There is as clear a difference in economic interest now as ever there was: indeed it is getting stronger. Twenty years ago, FTSE chief executives earned 17 times the pay of their workers, now they earn 75 times more. But no party has anything to say about that, none daring not to be the party of the rich. Yet great economic divides are there: the median earners on £22,000 and below are 50% of the voters - but that's a bit less than MPs get as expenses for running their second homes. So much gold dust is kicked in the nation's eyes by scores of TV programmes selling property beyond most people's imagining, or celebrity handbags costing thousands, that the delusion that most people are affluent has entered Labour's lexicon and even its soul. Labour needs a coalition of interests - but not to deny those interests.

Disgruntlement with politics may not express itself as a question of class, but it is the job of politicians to articulate people's strong if inchoate feelings, to crystallise ideas and describe society as it is. If they pretend that Britain is one great homogenous affluent bloc, with a few dysfunctional poor people to be sorted out, they sell a warped picture of the way we live now - and, instinctively, voters know it.