After the end of WWI and the global economic crisis of the 1920's many citizens in Europe didn't believe/or have trust in democracy,this is also when socialism starts to become widely accepted in the parts of Europe.

The Nazis were very hostile to democracy and viewed it as a very weak way to run a government and that it couldn't settle any issues and that communism was a Jewish tool to take countries. The NSDAP believed that their ideology was a perfect fit in between.

The Nazi ideology was extremely Nationalistic believing in the reunification of the German-speaking Aryan people. Hitler spoke of creating jobs for the unemployed (as long as the owners were not Jewish) and soon have economic prosperity and lessen the gap in the economic classes.

''Racialism and nationalism jostled shoulders with the socialistic revolutionary conservatism of many members of the Mittelstand (middle class). Romantic ideas came from right-wing youth groups. Hitler could utter the gospel of anti-capitalism to workers and the gospel of profits to businessmen. It was a rag-bag of inconsistent and incoherent ideas.'' -Walter Phillips.

Hitler being the very convincing person he was got many people to buy into these ideas. He told the people of Germany what they wanted to hear and he was so good at it he had supporters all over the globe.

TLDR: The NSDAP had many other beliefs then just Racialism and they played a big role in his rise to power.