[marron]

I can see a guy wanting to take a breath before lining up behind one or the other of his rivals.

He’ll presumably back the eventual nominee, though after the pounding he got from Donald it may be rather lukewarm support if Trump leads the ticket.

[TontoKowalski]

Nah. These guys are politicos. Rubio's feelings may be hurt, but if he has any plans for a future in politics, he'll be enthusiastically supporting the party nominee.