A Des Moines state senator says he's running for governor. Democrat Nate Boulton announced his candidacy with a video Thursday. He made a formal announcement in his hometown of Columbus Junction, embarked on a six-day trip that will take him to 16 cities around the state. Boulton says he's an advocate for working families who would prioritize support for education and worker training to make the state more economically competitive. The 36-year-old Boulton is a labor and workers compensation lawyer who's in his first term in state senate. He joins a Democrat primary field with former party chair Andy McGuire, activist John Niederbach, and Polk County Conservation director Rich Leopold.