The Washington Post has an interesting article detailing the 17-year history between Marco Rubio and Jeb Bush. The once-friendly mentor/mentee relationship came to a crashing halt during the CNBC debate when Marco Rubio, by many accounts, all but ended Jeb's presidential run.
The complaints from the Bush camp seem all-too familiar; that Marco's biggest sin was not to wait his turn. But as Marco Rubio himself has said, "Wait for what?"
Say what you want about the candidacy of Donald Trump, but his brashness in going after Jeb and the rest of the GOP field did the Republican party a service. It showed that Jeb didn't have the skills, or the fight, or the want-to, to play the political game at the highest level. It's better for the GOP to find that out now, before they give him the nomination, only to find it out and lose in the general election.
The biggest problem with the Bush campaign has always been the lack of a purpose behind it. Rather than running to continue a legacy or fix something that's broken, his reason for running has always seemed to be more based on the sense that, as a Bush, this is what he's supposed to do next.
GOP voters aren't buying it this year. If Republican voters aren't, general election voters certainly won't be either. Marco Rubio now seems to be the de-facto guy for the establishment and his poll numbers are going up. He was right not to wait. Jeb was never going to be the guy.