I will be shocked if Cruz is the nominee.
I'd be a bit surprised if Cruz isn't the nominee. Cruz is the second choice of all the candidates, so as people drop out, Cruz will benefit. Trump is far and away the most unlikable candidate, so who's votes is he going to pick up? Once the debate state gets down to 3-4, Trump will be forced to answer serious questions about his past, and even recent positions, for which he has no good answers. Just look at the recent Steven Colbert video of Trump debating Trump.
As of now, the race is between Cruz, Trump, and Rubio. Rubio has the Washington cartel backing, and If Trump drops out, his voters will mostly go to Cruz. At some point, the Trumpites will realize that Cruz will actually do what Trump claims he would do; because so far, Cruz has done everything he promised in his Senatorial campaign.