John Sidney McCain III (August 29, 1936 – August 25, 2018) was an American statesman who served as the senior United States Senator from Arizona, a seat to which he was first elected in 1986. He was the Republican nominee for President of the United States in the 2008 election, which he lost to Barack Obama.

McCain graduated from the United States Naval Academy in 1958 and followed his father and grandfather—both four-star admirals—into the U.S. Navy. He became a naval aviator and flew ground-attack aircraft from aircraft carriers. During the Vietnam War, he was almost killed in the 1967 USS Forrestal fire. While McCain was on a bombing mission over Hanoi in October 1967, he was shot down, seriously 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. The wounds that he sustained during war left him with lifelong physical disabilities. He retired from the Navy as a captain in 1981 and moved to Arizona, where he entered politics. In 1982,

McCain was elected to the United States House of Representatives, where he served two terms. He entered the U.S. Senate in 1987 and easily won reelection five times, the last time in 2016.

While generally adhering to conservative principles, McCain also had a media reputation as a “maverick” for his willingness to disagree with his party on certain issues. 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 resulted in passage of the McCain–Feingold Act in 2002. He was also known for his work in the 1990s to restore diplomatic relations with Vietnam, and for his belief that the Iraq War should have been fought to a successful conclusion. McCain chaired the Senate Commerce Committee and opposed pork barrel spending. He was a member of the bipartisan group known as the Gang of 14 which played a key role in alleviating a crisis over judicial nominations.

McCain entered the race for the Republican nomination for President in 2000, but he lost a heated primary season contest to Governor George W. Bush of Texas. He secured the nomination in 2008 after coming back from early reversals, but was defeated by Democratic nominee Barack Obama in the general election, losing by a 365–173 electoral college margin. He subsequently adopted more orthodox conservative stances and attitudes and largely opposed actions of the Obama administration, especially in regard to foreign policy matters.

By 2013, however, he had become a key figure in the Senate for negotiating deals on certain issues in an otherwise partisan environment. In 2015, McCain became Chairman of the Senate Armed Services Committee. He was diagnosed with brain cancer in July 2017; following the diagnosis, he took a reduced role in the Senate. McCain’s family announced on August 24, 2018, that he would no longer seek further treatment for his cancer to prolong his life; he died the next day at the age of 81, four days before his 82nd birthday.