This is a nearly impossible question to quantify due to a few reasons. Nevertheless two famous books, Hitler's Willing Executioners, and Ordinary Men, due a good, but very controversial and debated, presentation of how Germany as a whole went along with Nazi policy and ideology regardless of the party membership or political leanings of the average citizen.

But back to why this is hard to answer. The Nazi party never went above 10% membership quota of the population. This was a debate within Nazi leadership if the Party should be open to everyone as a true People's party, or take a more Vanguard Lennist-esque approach to having a smaller elite sector of the political leadership represent Nazi ideology for the rest of the nation. Ultimately, after Hitler rose to power and the Nazi party was the largest in the Reichstag, membership was capped at 10% as it had an explosion of membership applications. No doubt many opportunists saw the writing on the wall and wanted to be on the "right side" of German politics. Hitler recognized this and so agreed to limit party membership to curtail this. Only famously extending membership applications again temporarily before war broke out to gain more money for rearmament.

So the Nazi party is capped, but highly popular that more than 10% of the population tried, and would try to join it. What do we make of that? Well in the numerous plebiscites Hitler would have to gauge public opinion on his policy decisions, he would score in the 90% range consistently. Famously so on the question of the Anschluss. Of course, these are not free and private votes. The only option being ja or nein. And it is understood the Gestapo kept tabs on those who said no. But the desire of more than 10% of the population at any time in becoming an offical Nazi member combined with high yes votes, does present a theme here.

Further, while offical party membership may have been relatively exclusive, the numerous auxiliary party organs were not. The SA, the brown shirts of the party, until the Night of Long Knifes in Hitler's blood purge, actually had a larger membership than the official Nazis, and these were roudy violent people. Additionally, the Hitler Youth, save for kids in Catholic youth programs due to the Concordat, was mandatory for all minors. They were ruthlessly indoctrinated into Nazi philosophy, but many were never members when they turned 18 due to aforementioned party quotas. But they served in the Wehrmacht and civil society, and agreed with Nazi Weltanschauung, their world view.

Lastly Nazi Germany was not a free society, obviously, but that means its media and knowledge circulation was controlled by the state. News, opinions, entertainment, was all curtailed by the Ministry of Propaganda by Goebbels. Even if you weren't a Nazi, your knowledge of anything happening was filtered via Nazi bias before you consumed it.

So in the context of being called a Nazi in this environment moving moderates to that side? It didn't matter. Nazi domination was complete. If you mean in the heyday of the Weimar Republic as the Nazi party rose to power? Nazism didn't have a stigma like it does today. It was another political party. Horrifically violent, but so were the Communists. Its violence did go too far in the beginning after Hitler's failed Beer Hall Putsch and was banned for a little bit while he was in jail. So theoretically during that time being called a Nazi was an insult or attack on one's character, but at this point he was still obscure in German politics. Being called a Nazi didn't carry negative implications, the German public in large wanted to join the Party for the social and political privileges it brought.

The negative connotations were something Allied Propaganda and post war identity politics brought to the scene. For former Nazis, and those accused of being Nazis, had their lives on the line for the warcrimes they committed.