The United States Congress is the bicameral legislature of the federal government of the United States consisting of two houses: the lower house known as the House of Representatives and the upper house known as the Senate. Both representatives and senators are chosen through direct election. Congress has a total of 535 voting members: 435 members in the House of Representatives and 100 members in the Senate. Members of the House of Representatives serve two-year terms representing the people of a district. The founders of the United States intended the House to be the politically dominant entity in the federal system and, in the late 18th and early 19th centuries, the House served as the primary forum for political debate. However, subsequently the Senate has been the dominant body. Members of the House are elected by first-past-the-post voting in every state except Louisiana and Washington, which have run-offs. Elections are always held on the first Tuesday after the first Monday in November in even numbered years. The House has four non-voting delegates from American Samoa (1981), the District of Columbia (1971), Guam (1972) and the Virgin Islands (1976) and one resident commissioner for Puerto Rico (1976), bringing the total formal membership to 440. The Senate is the upper chamber in the bicameral