Both Republicans and Democrats appear to have concluded that their best strategy is to make their supporters feel more intensely committed and thus more likely to vote. For Mr Obama that means women, the young and African-Americans, for Mr Romney it means white working men, evangelicals, talk radio listeners and the better-off.
This is a questionable strategy. Democrats and Republicans have become more polarised and there are fewer of either of them. There has, instead, been a rise in the people that the political scientist James Stimson calls the Scorekeepers: pragmatic, coolly non-ideological, perfectly willing to shift from one party’s candidate to another. Where is the appeal to these people?”