There might not be one- to be more precise, there might never be a NSDAP- the term 'National Socialist' is probably too obvious not to be picked up by someone, but it might be a group with quite different ideas from the DAP lot (and it might not be a German group that popularises it, which would remove 'Nazi' from being anything but a Germanophone term)...
The DAP, meanwhile, most likely never gets off the ground, and stays a wierd left-extreme right minor party.
The hole left by the Nazis is filled by the Communists, the other right-wing authoritarian parties, possibly the *National Socialists, and, to some degree, maybe even the democratic parties!
Cue 1929, Hitler's American-bornity being insufficient to avert the Great Depression without butterflies, and things can go many different ways in Germany, not all of them ending in communist takeover, imperial restoration, or, for that matter, the end of democracy.
All this assuming minimal butterflies- if we do have butterflies, there's nothing saying the Great War will go as per OTL.