Father Charles Coughlin was an enormously popular Roman Catholic priest who hosted a nation-wide radio show in the 1930s and early 1940s. He was an arch-conservative and rather anti-semitic, yet managed to attract a fanatically loyal following, particularly in the urban Midwest. In the 1930s, Coughlin was responsible for the construction of a pilgrimage and faith center in Suburban Detroit, the Shrine of the Little Flower. Interesting design - I think it is in a style called "neo-Assyrian baroque."
Father Coughlin was vehemently opposed to President Franklin Delano Roosevelt, and resisted both the New Deal and Roosevelt's attempts to ease the United States out of isolation and formal neutrality. His magazine, "Social Justice," was ultimately suppressed on the grounds that it was deemed to be "fascist propaganda," and Father Coughlin was informally "silenced" by his Roman Catholic superiors in the Diocese of Detroit. Nonetheless, conservative Catholicism still has a very strong presence in Southeastern Michigan.