John Sidney McCain III (born August 29 1936) is the senior United States Senator from Arizona and presumptive Republican Party nominee for President of the United States in the upcoming 2008 election.

Both McCain's grandfather and father were admirals in the United States Navy. McCain attended the United States Naval Academy and graduated in 1958. He was married in 1965. He became a naval aviator, flying attack aircraft from carriers. During the Vietnam War in 1967, he narrowly escaped death in the Forrestal fire. On his twenty-third bombing mission over North Vietnam later in 1967, he was shot down and badly injured. He then endured five and a half years as a prisoner of war, including periods of torture, before he was released following the Paris Peace Accords in 1973.

Retiring from the Navy in 1981 and recently remarried, McCain moved to Arizona and entered politics. In 1982, he was elected to the U.S. House of Representatives from Arizona's 1st congressional district. After serving two terms there, he was elected to the U.S. Senate from Arizona in 1986. He was re-elected Senator in 1992, 1998, and 2004. While generally adhering to American conservatism, McCain established a reputation as a political maverick for his willingness to defy Republican orthodoxy on several issues. Surviving the Keating Five scandal of the 1980s, he made campaign finance reform one of his signature concerns, which eventually led to the passing of the McCain-Feingold Act in 2002.

McCain was a candidate for the Republican nomination in the 2000 presidential election, but was defeated by George W. Bush after closely contested battles in several early primary states. In the 2008 presidential election cycle, McCain was the Republican front-runner as the cycle began. His campaign suffered a near-collapse in mid-2007, due to financial issues and his support for comprehensive immigration reform. In late 2007, he staged a comeback. He won several key primaries during January 2008, and by the end of that month was the Republican front-runner once again. His lead was solidified by several victories on Super Tuesday in early February, and by the subsequent withdrawal of his closest competitor, Mitt Romney; he gained enough delegates to become the presumptive nominee on March 4, 2008.