Jeb is only mismatched cause Trump exists. Trump defined him early using his new found national voice and brought about the biggest upheaval in politics in ages for the GOP. Trump was blunt, vicious and unapologetic vs. Bush and made a moderate conservative vision of America unpopular within GOP group think (harnessed the anger on the fringe base). Trump went hard against him, unlike most others - and Trump was right on the money - taking out the establishment dream pick.
We saw the last debate. While not necessarily a home run, Bush had a solid performance. I personally think he won that debate. So if you take Trump out of the equation and the movement surrounding him; Bush, slowly but surely would of won the hearts and minds of the GOP voter base. Ted Cruz is and was too polished a politician, too PC to emulate Trump's fervor and brand.
Bush understands one thing, loyalty. The Cuban mafia in Miami bows to him (Ileana, Balart, you name it, he owns them), because he empowered them, helped them while being the big boss down here in Florida. Yet here comes little Marco (the apprentice, the student) upsetting the status-quo and somehow the very establishment that owes so much to Jeb (and the Bush family) wants him to give up everything he worked so hard for, built so tirelessly cause it's better for Marco? Please... How about what's best for Jeb?
What goes is Jeb's head and those loyal to him (his Pac) is, FUCK THEM. Fuck the sellouts, the snakes. Fuck the party and individuals that are deserting me when I am down. Fuck the ones that are not standing with me to take on Trump as I am, taking the blows that I am etc...
The strategy to sink establishment rivals is still the best viable strategy for him to get elected. In Jeb's view, he owes little to the detractors, little. Funny how Rubio and Jeb don't talk to each other after each and every debate. And it's not Rubio who's probably turning down such a encounter. Not to mention PAC money always has a use. After all, it would be foolish to think that this money is not enriching some folks in the ad-making, PAC running operations business etc etc etc. No refunds folks.