Four-term California Rep. Paul Cook is retiring from Congress to run for county office instead, continuing the stream of House Republicans heading toward the exit.

Cook’s chief of staff, John Sobel, told the Los Angeles Times that the congressman plans to run for the San Bernadino County Board of Supervisors. Sobel did not immediately respond to a request for comment.

Cook is the 13th House GOP lawmaker so far to announce his or her retirement. Like several other retiring colleagues, serving in the minority has been a new experience for Cook. He was first elected in 2012 after serving in the California State Assembly.

President Donald Trump carried Cook’s 8th District, which includes most of San Bernadino County, by 15 points in 2016, and the congressman won reelection last fall by 20 points. Inside Elections with Nathan L. Gonzales rates the 8th District race Solid Republican.

Cook wasted no time endorsing a successor. California Assemblyman Jay Obernolte listed Cook among his endorsements on his campaign website, which the Republican launched moments after the news of Cook’s retirement broke. Obernolte’s campaign site notes that his Assembly district overlaps with 65 percent of the 8th District.