Cruz is indeed likely to inherit the disaffected Trump vote.
Except that he is extraordinarily smart and he knows what he is doing–things that cannot be said of Trump. But Trump is serving a purpose: he is SO extreme and outrageous that he makes Cruz, the bete noir of the Left, look reasonable by comparison. Trump’s role is to make a Cruz presidency possible.
So I know that it famously has been falsely predicted many times, but I predict that Trump will crumble and that his minions will turn to Cruz. I think Rubio is too mainstream (though I am fine with him) and he probably won’t be able to overcome the “you got snookered on immigration” rap. Yeah, THAT is a huge problem right now. Jeb Bush is taking the fire as the establishment candidate, so Rubio is able to avoid that. That is Jeb’s contribution. He is a dead man walking–a bullet magnet that keeps Rubio in the hunt/public eye because of the comparison. Probably it will take a few more Presidential election cycles for Rubio to really emerge and be a force–though he might well be a VP candidate even now. He is a talent, that’s for sure.