As an evangelical, here is my perspective.
The Christians aren't voting based solely on their religion. For several elections (since Clinton) we've had it pounded into our brains by our leaders to "vote our values, not our wallets". What that did was push a large percentage of evangelicals to bring only a few issues to the forefront. Abortion is a big one. Gay mariage is another one.
For many who went along with that way of thinking, when they see a guy like Huckabee, they see someone like themselves (looking at the positives), which they trust.
We are in a battle of ideas. It's relatively easy to win over the apathetic or neutral types. It's much harder to convert those who have been voting a certain way, using a certain set of critieria. It will take time, truth, and tact (kindness) to win them over. Dismissing them as dumb, stupid sheep is only going to alienate them further.
A portion of them are not going to be winnable, but the ones who are open minded enough to be willing to look at things from a different perspective are ripe for the picking. But like I said, it will take time, truth and tact. Say it again . . . "Time, Truth and Tact!"