A special election happened on November 3, 2020 to elect a Senator from the U.S. state of Arizona. It happened because the last senator, John McCain, died in 2018. Primary elections happened on August 4, 2020 to choose who would run for the election from each party. The Republican Party chose Martha McSally. She beat Daniel McCarthy to be the Republican candidate. Only one person, Mark Kelly, ran for the Democratic Party.