If it was Hitler (R - authoritarian nationalist) vs. Stalin (D - communist), most would still cling to the idea that a third-party candidate was a wasted vote and choose their candidate by party.
This! The really scary thing about this election was that it was such an ordinary election despite extraordinary candidates. About 90% of traditional republicans voted for Trump and about 90% of democrats for Hillary.
Voting for a third candidate IS a waste because of the way your system is constructed. Why didn't Trump go as an independent? Because the right wing votes would have been split between him and the republicans and basically given the democrats the presidency. He would never have won as an independent despite having the same ideas, policies and interesting retorics.
There are so many things wrong with the system. The electoral college is one but the presidency itself is another. The presidency is a winner-takes-all competition where voting for a third party only increases the chance that your worst enemy becomes president instead of the dude you just dislike.
Switching to popular vote isn't enough. Candidates should be allowed to form coalitions after the vote is cast. That is, let all candidates run and if no one gets more than 50%, they can join forces and whatever group gets a majority decides on the presidency. Third, fourth and fifth candidates are not actively discouraged and all votes count. Having only two choices, isn't much of a choice at all. Especially when choosing between Stalin and Hitler.
A two party system is only one party away from being a dictatorship.