John Sidney McCain III (1936–2018) was an American politician and Vietnam War veteran who served as a United States Senator from Arizona from 1987 until his death in 2018 and was the Republican nominee for president in 2008. Known as a "maverick" Republican and maverick conservative, he was recognized for his bipartisan efforts and for positions such as campaign finance reform, and he was a prominent critic of Tea Party extremism. A leading hawk on foreign policy and defense issues, McCain advocated interventionist foreign policy, strong national security and military capabilities, and was a leading congressional advocate for regime change. During the 2008 campaign he hosted a Conference of Presidents conference call that faced criticism for being inappropriately partisan.