Progressive Party (United States, 1912)
As a member of the Republican Party, Roosevelt had served as President from 1901 to 1909, becoming increasingly progressive in the later years of his presidency. In the 1908 presidential election, Roosevelt helped ensure that he would be succeeded by Secretary of War Taft. After Taft took office, he hewed closer to the conservative wing of the party and this and other actions alienated Roosevelt from his former friend. Progressive Republican leader Robert La Follette had already announced a challenge to Taft for the 1912 Republican nomination, but many of his supporters shifted to Roosevelt after the former President decided to seek a third presidential term, which was permissible under the Constitution prior to the ratification of the Twenty-second Amendment. At the 1912 Republican National Convention, Taft narrowly defeated Roosevelt for the party's presidential nomination. After the convention, Roosevelt, Frank Munsey, George Walbridge Perkins and other progressive Republicans established the Progressive Party and nominated a ticket of Roosevelt and Hiram Johnson of California at the 1912 Progressive National Convention. The new party attracted several Republican officeholders, although nearly all of them remained loyal to the Republican Party—in California, Johnson and the Progressives took control of the Republican Party.
Populism
The People's Party of the late 19th century United States is considered to be "one of the defining populist movements"; its members were often referred to as the "Populists" at the time. Its radical platform included calling for the nationalisation of railways, the banning of strikebreakers, and the introduction of referenda. The party gained representation in several state legislatures during the 1890s, but was not powerful enough to mount a successful presidential challenge. In the 1896 presidential election, the People's Party supported the Democratic Party candidate William Jennings Bryan; after his defeat, the People's Party's support declined.
Other early populist political parties in the United States included the Greenback Party, the Progressive Party of 1912 led by Theodore Roosevelt, the Progressive Party of 1924 led by Robert M. La Follette, Sr., and the Share Our Wealth movement of Huey Long in 1933–1935.
In Canada, populist groups adhering to a social credit ideology had various successes at local and regional elections from the 1930s to the 1960s, although the main Social Credit Party of Canada never became a dominant national force.