A group of passionate Democrats contend with the consequences of the Republican federal government's sweeping social reforms

Hint 1: The Democrats are the protagonists in this film. Some people have suggested movies like "Lincoln" and "Free State of Jones" in which the Democrats were the antagonists, though their actions in those films do match the description. But no, in the film I'm describing, the Democrats are the protagonists, not the antagonists.

Hint 2: The sweeping reforms of the Republican federal government were pertaining to segregation, civil rights, and race.