Of course, there was the post-war Red Scare, the rebirth of the Klan, the anti-immigration laws of 1921 and 1924, Prohibition, etc., etc., etc. And with Teddy dead, Republican progressives loosened their ties to Republicans, a process that began with Wilson, and continued with Lafollette's ...(5/?)

..1924 independent campaign, then Al Smith in 1928, and then FDR and the Great Depression. While both parties remained wide coalitions, FDR's coalition had such disparate elements, such as Dixiecrats, northern urban liberals, and African-Americans, that it was inherently unstable. (6/?)