If they succeed then all bets are off and they will arrange to deliver the nomination to one of the challengers. It will destroy whatever vestiges of credibility the party has left, but they don't care about that anyway.
Exactly, Cruz knows it over, and he has joined the Cheap Labor Express, just as a lot of us knew he would.
Related:
http://www.freerepublic.com/focus/f-news/3402316/posts
Rick Perry opens door to convention in comeback in GOP presidential race