"A nazi walks into a bar, and is welcomed at a table by his nine friends. How many Nazis are at the table?" Anyone who sides with fascists, even tentatively or for differing reasons, is themselves still a fascist.
The German Nazis didn't gain power purely from support of other nazis; they gained power largely from various other parties, business leaders, and wealthy elite, who thought the Nazis would be a useful tool they could use and control to their own ends. The "why" of their support is far less important than the fact of the support itself, and the fact those people were responsible for helping the Nazis commit their crimes.