According to this memo in Phyllis Schlafly's Eagle Forum he has indeed:
I don't like Rubio. I don't care whether he's gay or not, but I do care that he does not appear to support the interests of We The People.
And I am highly concerned about the massive support he is receiving from "vulture fund" billionaire Paul Singer. I do not believe Mr. Singer has the interests of We The People in mind, either.