This has to be put to rest. While an 'outsider' will, clearly, have a difficult time with unfriendly D's and R's in congress, that is not to say an 'impossible' time. Anyone who wins the presidency, Gary Johnson, Ralph Nader, Ross Perot, will have ENORMOUS public support and to suggest that it won't phase the major parties is absurd. They will be confronted with the reality that enough people have had it with them, D or R, that their local existence will them be at risk unless they change and, to change, they will have NO choice but to play ball with the new president at least on some issues even if it is to only co-opt the issue which, in effect, will be the change we all seek. If not in name then in practice. Thereby, in the next election, if Gary Johnson succeeded in, say, reforming the Fed and it made things better, it will be with the help of both parties to some extent or one party to a large extent who will then stand to benefit.
Point is, they, the D's and R's, having lost the Big One, could not afford to stand pat. One or the other is going to try and cozy up. All a Johnson need do is stick to his platform. The other parties will come to him or go out of existence.