Rubio's young, and in it for the long haul. He really doesn't fit well in the mix this year, and his Senate seat is up in 2016. Rubio's a favorite for re-election to the Senate, but not a prohibitive favorite; the thing that boosts his re-election chances is the unlikelihood of a first-tier Democrat opponent.
Rubio's quite young. I can see him being re-elected, then moving into the Senate GOP leadership. He was speaker of the FL House of Reps, so he understands legislative leadership. The GOP needs a Hispanic face other than Ted Cruz, and Rubio foots the bill well. He could well end up having the most influential career of any Hispanic politician in history, and could well be President someday.
I think Rubio understands this. I think he knows that if he runs for President and loses, it won't be a plus, and will undermine his Senate re-election. I also think that serious donors understand this as well.
I don't think he cares about his Senate seat, or having a career in the Senate. He only ran for Senate in the first place in order to set himself up for a presidential run, IMHO.
From a distance, it may look that way. I'm a Florida resident, and I would respectfully (but heartily) disagree with you.
If Rubio really wanted to run for President in 2016, he'd have run for Governor of Florida in 2010. He could have run for either. The Governorship was open, he was a former Speaker of the Florida House, and Charlie Crist had announced for the Senate and was, initially, an overwhelming favorite.
Rubio was a conservative who caught a Tea Party tailwind. Florida's GOP conservatives found Crist to be more of a moderate Republican than they thought he'd be, and got behind Rubio, forcing Crist to run as an independent. (Crist lost his advantage and decided he'd be better off in a 3 way race, because the AG McCollum and the wealthy Scott made it impossible to re-enter the Governor's race.) But his experience was in state politics; he just didn't want to get lumped in with the Scott-McCollum antipathy. Besides, the Democrat running for Senate (Rep. Kendrick Meek) seemed easier to beat than Chief Financial Officer Alex Sink.