I think that Rush is being eminently fair to both Cruz and Trump. As one who could vote either way, I think he does a very good job of backing both of them against unfair criticism. He also is an equal opportunity criticizer of both.
Anyone who says that he is overtly for one or the other just sees what they want to see (as Rush himself has mentioned many times).
When I listen to someone for 3 hours and only hear praise of Cruz, I don’t think I am hearing it wrong.