It’s not like antisemitism prevented people from supporting the NSDAP (in many cases the opposite). Sure, when they were elected they didn’t know what to do with Jews yet, but antisemitism was one of the pillars of their philosophy (if the people are unhappy you have to take responsibility or simply point at someone and say “they are responsible, it’s their fault”) and antisemitism has existed since forever. (Of course there were not only Jews in concentration camps but they were initially made for them).