I don’t think this type of process will be damaging to the Republican nominee. I could easily see the party uniting behind someone (even someone I don’t like) and quickly facing the Dem opponent. It must be hard for Hillary and the DNC right now not to know who to turn their guns on.
I think most people will unite behind the Republican candidate even if it is not their first choice, with the exception of RP who said on Neil Cavoto’s(?) show, he would not.