By the 1920s, the emerging middle and working classes were powerful enough to elect a reformist president, whose program was frustrated by a conservative congress. In the 1920s, Marxist groups with strong popular support arose. | By the 1920s, the emerging middle and working classes were powerful enough to elect a reformist president, whose program was frustrated by a conservative congress. In the 1920s, Marxist groups with strong popular support arose. |