There is an electoral majority to be had without them AND their supporters.
If one is to truly remake a party, one must not only vanquish the opposition, but expunge them...and then win without them. They must be isolated and completely without influence.
Cruz and his supporters have chosen this fate for themselves. They will be expunged and the nominee will go on to a general election win.
I agree 100%, we should move forward without them. Those who wish to join us are welcome, but to those who don't we need to treat them with suspicion and as potential enemies.