In recent election cycles the term "populist" has been applied to such varied figures as John Edwards, Mike Huckabee, Patrick Buchanan, and Ross Perot, arguably sharing a sort of economic nationalism for the poor. Originating in anti-aristocratic agrarian movements in Europe, especially the Russian Narodniki of the late 1800s, the movement in the US attempted to encompass the urban working class as well, as symbolized by the rural Scarecrow marching along with the urban Tin Woodman on the Yellow Brick Road to defeat the Wicked Witch of the East, with populist heroine Dorothy and the Cowardly Lion stand-in for fundamentalist and anti-imperialist populist William Jennings Bryan, he of the "Cross of Gold" speech, in Baum's populist fantasy novel. The movement would be partly absorbed by the later Progressive and New Deal movements.
The movement has always had a deep divide, with race the central issue. So, on the one hand we have the progressive wing, symbolized by the remnant Democratic-Farmer-Labor Party of Minnesota and the presidential candidacy in 1948 of FDR's former Ag Secretary, Henry Wallace for the Progressive Party. On the other, in the Deep South, we got "Pitchfork" Ben Tillman in South Carolina, whose follower, Strom Thurmond, would run as the "Dixiecrat" in the 1948 presidential campaign. Today, this divide most clearly shows up in the struggle over immigration.