Walters, whose 37th District includes Costa Mesa, Newport Beach and portions of Huntington Beach and Laguna Beach, is looking to succeed U.S. Rep.
Orange County District Attorney Tony Rackauckas, Sheriff
Supervisor John Moorlach, a Republican and Costa Mesa resident, has also said he's eyeing a run for the congressional seat. The District 2 representative doesn't live in the 45th Congressional District, though federal law does not prevent him from running for the seat.
Campbell, who is finishing his fifth term, said in July that he will not seek reelection.
Cities in his 45th District include Irvine, Tustin, Lake Forest, Mission Viejo and portions of Anaheim and Orange.
Walters was elected to the state Senate in 2008 after serving in the state Assembly. She began her political career on the Laguna Niguel City Council in 1996.