I am not convinced he ‘turned’.... I think he is very calculating about who he can ‘hook’ into filling his bank account. Now that it is filled he can be who he has been all along.
My thoughts about Rush: He desperately wants another Reagan conservative at the helm to correct the Obama/Clinton harm. Trouble is the two conservatives he likes the best are damaged. Therefore, he is attempting to make them more palatable to the listening audience. He sees Trump as a spoiler in this election who is more showman than substance but also knows over half his audience supports the man. What does Rush do? Big problem for him. Maybe he believes Rubio has changed. Trouble is not even Rush has foreseen the level of anti GOPE in the country.