As I recall, the current president was a young, first term senator.
The difference is that he can think and reason, and articulate the conclusions he comes to. Rubio, on the other hand is a robot, mindlessly repeating the same message over and over.
So Rubio LOOKS too young and ACTS too young. Obama, on the other hand, looked and acted mature.
Rubio is doing one thing and only one thing here: political triage. He is on track to lose badly in Florida and he knows it. He’s already given up his chance to run for reelection in the Senate and if he gets shellacked in Florida, there goes his chance of running for governor in two years. He’s out of politics.