Not to put you on the spot.... but do you have a bit of the transcript or a link that would back up your claim? I remember that Rush was careful NOT to come out in support of any one candidate during the primaries. Now.... that doesn't mean that Rush may not have defended one of the candidates (even Trump) against charges or lies by the rabid left during that time.
Rush lauded all the 17 candidates as 'better than Hillary', it was self-evident early-on that Trump was the guy he was supporting - even after he said that Rubio was a 'full throated Conservative' and said Cruz was the closest to Reagan. I began to see it was just placating his audience and supporting the party rather than any principles. His daily amusements and defenses of Trump made it very obvious whom it was he was supporting.
I know what I heard, because within a minute of his remarks on the day I got pissed, I logged into my account to cancel my 24/7 membership. Several weeks later right before the convention when some lady called up and said if Trump was the nominee there was no way she was voting for Trump and Rush said that she was then voting for Hillary, I immediately turned off his radio show for good. I haven't listened since. I'm not going to spend the time to dig through his show transcripts to justify my actions, you are welcome to do so if you like.
He has absolutely no credibility with me any more. None.