That tends to validate my alternative scenario that Mitt Romney would fare much better in affluent suburbs than Republican nominees since 1992, running more like George Bush did in 1988. The only way Pennsylvania and Michigan can be close is if Obama’s support in affluent Philadelphia and Detroit suburbs has melted away.

This also helps explain why Romney still narrowly trails in Ohio polls. Affluent suburban counties cast about one-quarter of the votes in Pennsylvania and Michigan but only one-eighth in Ohio.

A pro-Romney affluent swing is confirmed by the internals of some national polls. The 2008 exit poll showed Obama narrowly carrying voters with incomes over $75,000. Post-debate Pew Research and Battleground polls have shown affluent suburbanite Romney carrying them by statistically significant margins.

In particular, college-educated women seem to have swung toward Romney since Oct. 3. He surely had them in mind in the foreign policy debate when he kept emphasizing his hopes for peace and pledged no more wars like Iraq and Afghanistan.