Democrat Kyrsten Sinema and Republican Martha McSally, both current members of Congress, are locked in a tight contest in the race to succeed retiring Arizona GOP Sen. Jeff Flake. McSally, who touts the endorsement of President Donald Trump despite refusing to say whether she voted for him, has represented a Tucson-area seat since 2014, and long before that was the first woman ever to fly combat missions as an Air Force fighter pilot.