Just a reminder, Marco Rubio only became a Senator in 2010 because of low turnout amongst minorities angry about the Great Recession and because Democratic voters divided their votes between Kendrick Meeks and Governor Charlie Crist. And even then he only won with 48.9% of the vote.
2016 is going to be a very different election, especially if Clinton is at the top of the ticket and especially with newly elected DEMOCRATIC (and pro marriage equality) Governor Charlie Crist rallying Democratic voters.
If the Florida Democratic Party gets their shit together and if a strong candidate goes up against him, Rubio is in deep shit.
Forget about being president. Rubio has a 50/50 chance of being a one term Senator.