The US has overcome really strong fascist currents before by organizing at the grassroots level and taking direct action. There are many people talking about how this could be accomplished and supporting the public with resources. This video popped up in my feed and reminded me: youtu.be/NPmzs9QHNTU
Organizers back in the day of a powerful Klan and packed-house Nazi rallies in Madison Sq Garden didn't have the benefit of all the resources and knowledge we have access to now. I believe it is well within our power to reclaim the democracy we deserve without waiting for the Dem party to do it.
But then the govt was opposed to the Nazi's instead of like now, when the Nazi's ARE the govt! There are no historic parallels we can draw on but one: fascists only understand hard power; pieties & never ending legal actions have never stopped them
I recommend you Rachel Maddow's podcast Ultra and/or her book Prequel, which will disabuse you of the notion that the govt was not in an existential struggle against fascism from within before and during WW2.