First, Huckabee is a total government-as-Christian-operative kind of guy, and that plays into the Libs hands by drawing the social conservatives into the Liberal ideological camp in a very deceptive way.
Second, Huckabee is an ex Baptist minister and the Libs )media Libs primarily, think the NYT) will raise endless questions about what that might mean for the “separation of church and state”, blah blah blah.
I think many Christians see in Huckabee the possibility of finally getting “one of their own” and don’t think much beyond that.
I will admit that the first time I saw the Huckster in the first two debates I kind of liked him and his relaxed style. It was only later when I learned the facts about his record as governor of Arkansas that I listened more closely and realized Huckabee was in many way just another Bush style “compassionate conservative” and not a real conservative.
You are more correct than you know...there are other reasons, too. If you can stomach the Huckabee related opinions spewing forth from the Kossacks at the Daily Kos, you'll see what I mean.