The veneer of friendship between Jeb Bush and Marco Rubio is beginning to peel. Bush has started taking swipes at his former protégé, who has emerged as a serious threat to his presidential aspirations as a fellow establishment candidate who appeals to the same pool of donors seeking to keep the likes of Donald Trump and Ben Carson off the November 2016 ballot. "Suppose it's a close vote; both will survive to fight elsewhere," says political scientist Larry Sabato of the University of Virginia. "Of course, neither candidate will be able to explain away a decisive l...
