The 2010 United States Senate election in Arizona took place on November 2, 2010, along with 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. The primaries were held on August 24, 2010. Incumbent Republican U.S. Senator John McCain, who had lost the 2008 United States presidential election to then-United States Senator from Illinois Barack Obama, ran for reelection to a fifth term and won. As of 2022, this was the last time the counties of Coconino and Pima voted for the Republican candidate.