By Rebekah L. Sanders | The Arizona Republic
The first challenger for Rep. Raul Grijalva‘s southern Arizona seat in 2014 has announced her candidacy. Gabriela Saucedo Mercer will launch her campaign at a Tucson event Saturday at noon at the Four Points by Sheraton hotel, 7060 S. Tucson Blvd.
Mercer, a Republican and political newcomer, ran against the longtime Democratic congressman unsuccessfully last year. She is a Mexican native who became a naturalized U.S. citizen.