Everyone assuming Trump will win WV in a landslide is mistaken. They directly elect delegates, not vote for a candidate. This could be a Cruz victory because of his ground game.. Also, the rest are Cruz country.
In WV, they indeed elect directly delegates but on the ballot this is written for which candidate they're going to be bound.
In Nate Silver's state-by-state guide, he noted that there are a whopping 220 at-large delegate candidates on the ballot, and voters pick 22(!). If that's true, I could imagine a big undervote, owing to voters not wanting to bother with a big and confusing delegate list after they've voted for their presidential candidate of choice. Having a targeted informational campaign to inform one's voters about this could prove useful.