[rdl]

I'm not sure if anyone could really stand up to the rest of Washington for 8 years, without going in as such a zealot in some way that you might not really want them as President.

Ted Cruz/Paul Ryan/Ron Paul might be the closest thing to that. Bernie Sanders, maybe, although I'd have a hard time seeing him maintain an 8 year long fight. Everyone else is basically establishment to some degree (Trump doesn't strike me as ideological as much as opportunist++, although certainly different in style than the others.)

(And maybe you want someone reasonable/rational/etc. but not ideological as President.)

[rapind]

I think Sanders could maintain. I could be wrong, but he has a pretty long record of doing the right thing (from my perspective) and I'm not sure what else you're supposed to vote for if not his / her record? Charisma? Promises? Anger?

[rdl]

I think Sanders is more ideological than most credible candidates in history (which is a lot of the appeal); same as Ted Cruz. (just polar opposites on ideology)

They're both pretty exceptional as top-2 candidates for their party nomination for that reason, compared to historical trends.

[rapind]

Agreed on Sanders. I probably would have picked Rand Paul as the opposite though.