head of government: President Barack H. OBAMA (since 20 January 2009); Vice President Joseph BIDEN (since 20 January 2009)
cabinet: Cabinet appointed by the president with Senate approval (For more information visit the World Leaders website ) elections: president and vice president elected on the same ticket by a college of representatives who are elected directly from each state; president and vice president serve four-year terms (eligible for a second term); election last held 4 November 2008 (next to be held on 6 November 2012)
election results: Barack H. OBAMA elected president; percent of popular vote - Barack H. OBAMA 52.4%, John MCCAIN 46.3%, other 1.3%;
Legislative branch:
bicameral Congress consists of the Senate (100 seats, 2 members elected from each state by popular vote to serve six-year terms; one-third elected every two years) and the House of Representatives (435 seats; members directly elected by popular vote to serve two-year terms)
elections: Senate - last held on 2 November 2010 (next to be held in November 2012); House of Representatives - last held on 2 November 2010 (next to be held in November 2012)
election results: Senate - percent of vote by party - NA; seats by party - Democratic Party 51, Republican Party 47, independent 2; House of Representatives - percent of vote by party - NA; seats by party - Democratic Party 192, Republican Party 243
Judicial branch:
Supreme Court (nine justices; nominated by the president and confirmed with the advice and consent of the Senate; appointed to serve for life); United States Courts of Appeal; United States District Courts; State and County Courts
Political parties and leaders: