As Republican presidential candidates crisscross the nation to win key GOP strongholds, an analysis of the party’s own delegate rules reveals that Blue State Republicans have vast power to pick the party nominee. That’s good news for pragmatic, moderate Republicans such as a Jeb Bush, but not for conservative or religious candidates, such as Ben Carson. It also means that the eventual nominee could be very different from the leader in national polls because a candidate getting a few votes in the right (moderate) places can get as many if not more delegates than a candidate getting more votes in...