Arizona gained one seat in redistricting due to rapid population growth, and the state's independent commission drew a seat that could be winnable by either party. Rep. Ben Quayle (R-Ariz.) was drawn into that new district, but has signaled his plans to run in a neighboring district instead.

The National Republican Congressional Committee wasted no time in shooting down Sinema's candidacy, calling her a rubber stamp for Obama and alleging she would be a bust for job creation.