Then they're astonished to see their candidate can't get 10% of the vote in a primary.
All of my evangelical friends kept telling me that Huckabee was going to "take off" among the general population. They kept saying that it was only a matter of time before non-evangelicals flocked to him. They kept insisting that he was the next POTUS. None of that ever happened. They just couldn't understand that the vast majority of the populace simply doesn't think like them. Sort of like the people who think a nationwide "revival" is always around the next corner, when in reality, religion in America will probably go the way of European Christendom.