John Sidney McCain III  is the senior United States Senator from Arizona. He was the Republican nominee for president in the 2008 United States election.  McCain followed his father and grandfather, both four-star admirals, into the United States Navy, graduating from the U.S. Naval Academy in 1958. He became a naval aviator, flying ground-attack aircraft from aircraft carriers. During the Vietnam War, he nearly lost his life in the 1967 USS Forrestal fire. In October 1967, while on a bombing mission over Hanoi, he was shot down, badly injured, and captured by the North Vietnamese. He was a prisoner of war until 1973. McCain experienced episodes of torture, and refused an out-of-sequence early repatriation offer. His war wounds left him with lifelong physical limitations.

He retired from the Navy as a captain in 1981, moved to Arizona, and entered politics. Elected to the U.S. House of Representatives in 1982, he served two terms, and was then elected to the U.S. Senate in 1986, winning re-election easily in 1992, 1998, and 2004. While generally adhering to conservative principles, McCain at times has had a media reputation as a "maverick" for having disagreed with his party. After being investigated and largely exonerated in a political influence scandal of the 1980s as a member of the Keating Five, he made campaign finance reform one of his signature concerns, which eventually led to the passage of the McCain-Feingold Act in 2002. He is also known for his work towards restoring diplomatic relations with Vietnam in the 1990s, and for his belief that the war in Iraq should be fought to a successful conclusion. McCain has chaired the Senate Commerce Committee, has opposed spending that he considered to be pork barrel, and played a key role in alleviating a crisis over judicial nominations.

McCain ran for the Republican presidential nomination in 2000, but lost a heated primary contest to George W. Bush. He secured the nomination in 2008 after coming back from early reversals, but lost to Democratic candidate Barack Obama in the general election.