The Byrd machine, or Byrd organization, was a political machine of the Democratic Party led by former Governor and U.S. Senator Harry F. Byrd (1887–1966) that dominated Virginia politics for much of the 20th century. From the 1890s until the late 1960s, the Byrd organization effectively controlled the politics of the state through a network of courthouse cliques of local constitutional officers in most of the state's counties.