You've got a slipping Republican second-place man who is a johnny-come-lately to the conservative fold. The conservative establishment isn't sure whether to trust him, but they trust him more than the front-runner. There's also the basic suspicion about his religion, which to many Christians' standards isn't really Christian.
You've got someone who was a dark-horse third place Republican candidate, but he's (by some counts) neck-and-neck in the delegate count with the second-place guy, and the conservative establishment hates him too. They're also pissed because he played a more successful political game in West Va than his opponents. Backroom deals? There's a pot and a kettle out here...
Finally, you've got a kooky last-place Republican candidate who may pull enough delegates to have a voice (if not a chance) at the convention. Yep, you guessed it, the conservative establishment hates him too.
I forsee a lot of disillusioned Republicans. Maybe so disillusioned even the spectre of Hillary Clinton can't rouse them...