His delegate games are threatening to undermine faith in the party, and I'll give it to those "insiders," they do love the party.
Interesting poll discussed on CNN. Both R's and D's think their primary elections are rigged. But D's believe that 20% more than the R's. That's going to be a bigger hurdle for Hillary to overcome. With the R's the hurdle isn't so big, because the "victim" of the rigging is winning.
Those issues are going to persist in the states wehre he played those games, just as Ron Paul zealots created some issues.
And if the party allows Cruz to control the convention, you better believe it, the people will see that as the party facilitating the shenanigans, against popular will.
At any rate, my general point is that the party has more control over this than Cruz does, and Cruz really has not the power to damage the party. Cruz staying in does not damage the party, the party still has control of its own fate.