It is possible Trump has "changed". I hope so. However, I do hope Cruz can make his stand and go all the way.
Trump may have had a come to Jesus with his past positions. I hope he has. Personally I don’t think we should elect him to see whats in him, to paraphrase the not so great Pelosi. It may be a hard lesson if it goes sideways.
I think Cruz can. But he needs people to stand on principle on his behalf/primary and beyond. And that is in short supply.