Yeah but much more than that:
1) Cruz didn’t accomplish anything in the senate. People had real questions about whether he would be as ineffective in the presidency.
2) Cruz didn’t attract evangelicals as he should have. This was due to a) some evangelicals seeing the issues of security and rebuilding the economy as THE key “evangelical” issues-—and Trump seemed stronger-—and b) I do think the sneaky “dirty trucks” caught up with him. I said over and over: other candidates could get away with that stuff because they weren’t running as “the pious/moral” candidate.
3) Cruz rightfully had enough “mainstream/GOPe” baggage & support to indeed make him look like an insider.
4) Naming Fiorina early and doing the deal with Kasich made him seem desperate.
I could give more, but Rush owed it to his audience to at least ACKNOWLEDGE that these were real factors.