That question doesn't make any sense. Why would they ever try to "court" someone who they know is already going to vote for them no matter what? It's precisely the undependables that need courting.
Moderates who can't stand the far left seem to be a much more solid base from their viewpoint. In light of this, it would appear that we shouldn't be suprized when the moderates are the people to whom RNC decides to kow-tow.
Threatening to leave isn't much of a threat to the party leadership since these people were never there to begin with. It is our job to convince them that we are valuable. It is pretty late in this election cycle to try for such a sea change, though.