Cruz is slow but steady. A couple of months ago he was in 8th place and at risk of falling to 11th and out of the first Big Boys debate.
Right now on RCP he is in 4th and homing in on Rubio, the current 3rd place holder.
Fiorina is falling like a rock.
Bush is fading
Walker is gone
Paul, Huckabee, Kasich and Christie are finished
Trump has pulled nearly all the oxygen out of the Conservative Room. Carson grabbed some of it and Cruz has picked up the crumbs. But they are solid, loyal crumbs. He will advance if either Carson or Trump start to slip. With Carson that is likely. With Trump that is possible.
You have the best analysis. The ‘front runners’ aside from Trump and Carson are more or less media/establishment creations. Kristol still pushing Rubio/Fiorina. I do think Cruz supporters are steady and not easily swayed and are more than it appears. He may not win but he has my vote.