It wasn't just the holocaust that made Jews sympathetic to civil rights protest. Even in the US, Jews were subject to some of the same discrimination as blacks. There were restrictive deeds which prevented Jews from owning property in certain areas. There were quotas on college admissions of Jews because admitting people based on objective criteria lead to too many Jews and not enough of the "right people" being admitted.
My grandfather was Jewish. My grandmother was a Methodist minister's daughter. When they married in 1929, both of their families thought they were nuts. However, one of the tricks they used to beat restrictive deeds was funny. They lived wherever they wanted to live. If the deed or lease said no Jews, my grandmother bought the property or signed the lease by herself. She wasn't Jewish. Restrictive deeds were outlawed by the Civil Rights Act of 1964