Republican Party (United States)
Founded in 1854, the GOP originally subscribed to classical liberalism and took ideological stands that were anti-slavery and pro-economic reform. Abraham Lincoln was the first Republican president in the history of the United States. The party was usually dominant over the Democrats during the Third Party System and Fourth Party System. In 1912, Theodore Roosevelt formed the Progressive ("Bull Moose") Party after being rejected by the GOP and ran as a third-party presidential candidate. Roosevelt called for many social reforms, some of which were later championed by New Deal Democrats in the 1930s. He lost the 1912 election, and when most of his supporters returned to the GOP, they were at odds with the party's new conservative economic stance; many left for the Democratic Party, and an ideological shift to the right occurred in the Republican Party. Later in the 20th century, the liberal Republican element was overwhelmed by a conservative surge begun by Barry Goldwater in 1964 and continued during the Reagan Era.
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.