Maricopa County Treasurer David Schweikert (R) is exploring a bid for the 5th district, joining a growing list of Republicans interested in taking on Rep. Harry Mitchell (D).

Mitchell, who ousted then-Rep. J.D. Hayworth (R) in November in the GOP-leaning Phoenix-area district, is girding for a tough re-election battle, and had stockpiled $531,000 in his campaign account at the end of the second quarter.

Also running, or considering running, on the Republican side are state Rep. Mark Anderson, Tempe Mayor Hugh Hallman, state Corporation Commissioner Jeff Hatch-Miller, former state Rep. Laura Knaperek, Sean Noble, who is chief of staff to Rep. John Shadegg (R), lobbyist Jim Ogsbury, state Rep. Michele Reagan and former Rep. Matt Salmon.

— David M. Drucker