The Republican Party in the United States includes several factions, or wings. During the 19th century, Republican factions included the Half-Breeds, who supported civil service reform; the Radical Republicans, who advocated the immediate and total abolition of slavery, and later advocated civil rights for freed slaves during the Reconstruction era; and the Stalwarts, who supported machine politics.
In the 20th century, Republican factions included the Progressive Republicans, the Reagan coalition, and the liberal Rockefeller Republicans.
In the 21st century, Republican factions include conservatives (represented in the House by the Republican Study Committee and the Freedom Caucus), moderates (represented in the House by the Republican Governance Group, Republican Main Street Caucus, and the Republican members of the Problem Solvers Caucus), and libertarians (represented in Congress by the Republican Liberty Caucus). During and after the presidency of Donald Trump, Trumpist and anti-Trumpist factions arose within the Republican Party.