I picked up on Rush tipping the scale for Cruz. This is so unusual for him. It is as if everyone is totally nuts in this election cycle.
It really is. He's never come this close to making an actual endorsement in a primary before. He's got to know that it's going to cost him listeners, which is why he's never done it before.
As a well known media personality, it just makes sense to hold your cards close to your vest until the nominee is chosen. Indicating, or even hinting at your personal choice during the primary, is just bad business, because you're going to drive away a portion of your listeners.
Perhaps Rush has just gotten to the point where the money and listener numbers just aren't all that important any more. He's got to know that this is going to hurt his show.