A former Arizona lawmaker says she'll challenger U.S. Rep. Tom O'Halleran in the Democratic Primary.
Barbara McGuire announced her plans on Friday and noted that O'Halleran is a former Republican.
Arizona's sprawling 1st Congressional District includes northern and eastern parts of the state, as well as much of Pinal County south of Phoenix. Republicans and Democrats are closely matched in the district, which the GOP is targeting as a potential pickup in next year's election.
McGuire says she's an effective advocate for rural Arizona.
McGuire joins a primary that includes former Flagstaff city council member Eva Putzova.
O'Halleran won a second term in Congress last year, defeating Republican Wendy Rogers 54% to 46%. He previously served in the state Legislature as a Republican before switching parties.
Two Republicans are also campaigning for the seat, Safford City Council Member Chris Taylor and Pinal County lawyer Tiffany Shedd.
Former Major League Baseball pitcher Curt Schilling has expressed interest in running for the seat as a Republican also.