And I speak this as one who likes Ted Cruz and he is still at the top of the list of my favored candidates (as I posted earlier today).
I can understand the number of times Trump had to respond since most of the questions Tapper asked had to do with Trump. I think Cruz needs to get more aggressive. I understand why he's playing the "nice" card in regard to Trump and other Republicans and he has been smartly insightful to do so, but a lot of his popularity has come from the fact that he has not been playing the "nice"guy and has labeled people, like McConnel or Graham, for what they are. Cruz has a lot of supporters, but money is political oxygen in modern politics. If Trump doesn't implode like the establishment Republicans think, then Cruz could end up losing some financial backing to people like Jeb Bush or now Carly Fiorina because they will have an early lead over him and many partisan donors would rather just see a party win, rather than ideology..
This graph comes from FiveThirtyEight