A front-page story in the Wall Street Journal features this chart:
It shows, as the Washington Post bannered after the 2006 election, that evangelicals moved a bit away from the Republicans in 2006. Indeed, there was a 7-point decline in the Republican margin among evangelicals.
But if you want to see a real shift, the Post and the Journal could run this chart:
In other words, among libertarians, the margin for Republican House candidates dropped from 47 to 8 points, a 39-point swing. The libertarian vote is about the same size as the religious right vote measured in exit polls, and it is subject to swings more than three times as large. Strategists in both parties should take note.