I don't honestly think there's any other possibility.
Or perhaps not...Therein lies the rub, and while you'll likely think I have my head in the sand, here, I persist in thinking that:
A) One must first be elected to office before one can effect change...
B) Until a real "firebrand" third party candidate with a significant grass-roots base is able to translate this into a national following, this will not be possible (think Perot and Nader)...
C) Voting for third party candidates in State/National elections will almost always result in a "split vote" between the two most compatible candidates, thus assuring election of and representation by the candidate most in opposition.
IMHO, the "inevitable" for the moment is (for example) "prescription drugs for seniors"...this issue can be addressed by Republicans, "RINO's", or Democrats, (or Bernie Sanders...the currently sitting "third party candidate!) but it will need to be addressed one way or the other. I would far prefer even a "RINO" plan to a liberal Democrat (or Socialist) plan, if plan we must...for one thing, the odds are much better that it will not be written in stone, and for another thing, I'm unconvinced that if the US is turned into "shattered remnants of [a] nation", it would be possible in this day and age to rebuild it...