The key phrase is “multi-party democracy”. I guess I should have also added “parliamentary” into that phrase. Political systems with a single winner are far more prone to electoral manipulation than systems where a coalition government is the norm.

I wouldn’t see it too tragic. Those who would support AfD already do, and the rest won’t change the mind because of an article written in a lunatic’s name. If he threw considerable amount of money at AfD, I’d get a bit concerned, but in a functional multi-party democracy, especially one with a nazi past, a nazi party would never be invited into a government unless it won an outright majority.