Jeb Bush will get a big push beginning in about 6 weeks. We have yet to see the full force of the Bush campaign.
I honestly believe that the nominee will be Bush, but if they decide he is not their man after all, then Rubio is the safe backup plan. But there is no way that Trump will even be anywhere in sight once this thing gets going. Neither party ever nominates a total outsider, someone they can't trust. Reagan was not an outsider in 1980, and he proved it by putting Bush on the ticket and in many other ways prior to that.
Governor Bush, didn't you say you had cool things you could be doing rather than running? I don't think posting on Atlas counts.