I'd like to add that economic pressure is useful too. Try to boycott companies that support genocide. Individually it isn't much but if you follow Andrew's guidelines then you will hopefully influence others to do the same.
Do not forget that in '32 the SPD backed Hindenburg... who then nominated Hitler as chancellor.
Thälmann was foolish, but even if he didn't run, Hitler would still get into power. If the far right is strong enough, mere electoralism will not stop them. Fighting them must happen on the street level.
I agree. I should also note that it is not useful to treat them as fascists. Right-wing and left-wing authoritarianism spring from different mindsets and combatting them requires different approaches.
That being said, there are intersections. The most notable are the nazbols, patsocs, and strasserites. It is absolutely appropriate to refer to such groups as red fascists.
Every day I find a new reason to hate the US government.