The 2004 United States Senate election in Arizona took place on November 2, 2004 alongside other elections to the United States Senate in other states as well as elections to the United States House of Representatives and various state and local elections. Incumbent Republican U.S. Senator John McCain won re-election to a fourth term with his largest victory as a U.S. senator.
Since 1998, McCain had an eventful third term. He challenged Texas Governor George W. Bush in the Presidential primary and despite winning the New Hampshire primary, he lost the nomination. Solidifying his image as a maverick, he voted against the Bush tax cuts. He supported limits on stem cell research. He had a lopsided favorable ratings of 39% to 9% unfavorable in the most recent New York Times/CBS News poll.
Stuart Starky, an eighth-grade teacher in South Phoenix, was widely known as a long-shot challenger. Starky stated that "I truly believe he's going to run for president again." Starky was called by The Arizona Republic a "sacrificial lamb" put on ballot because there were no chances to beat McCain. During his campaign, he debated McCain twice, once in Tucson and once in Flagstaff. He was also featured on the cover of Teacher Magazine, dubbed the "Unsinkable Stu Starky." Starky was defeated in a landslide. But, despite the relatively low percentage, he gained the highest vote per dollar amount in the country, spending only about $15,000 for his campaign (Starky's campaign may have been aided by John Kerry running for president).