Exit polls from the Alabama Senate special election on Tuesday show that Roy Moore got 80 percent of the white evangelical vote, but nonetheless went down to defeat. This is shocking, because white evangelicals are a big share of Alabama’s population. Indeed, public polling on religion suggests Alabama should be the third-strongest-state for white evangelicals! Only Tennessee, West Virginia, and Arkansas have more of us than Alabama has. So if it’s a big voting bloc and they’re 80 percent for a candidate, shouldn’t that candidate win?
This is where opinion polling gets tricky. The exit poll from Alabama shows that white evangelicals made up about 44 percent of the electorate, versus somewhere between 35 percent and 47 percent of the general population, depending on which polls and methods you use. White evangelicals were probably slightly over-represented in the electorate versus their population share, indicating they had higher turnout than other groups did.
With high turnout and 80 percent in favor of a candidate in a group that is a large population share, victory should be assured. But it was not to be.