A Democrat, Sterling defeated former Governor Miriam "Ma" Ferguson and several other candidates in the 1930 primary race for governor. During Sterling's term in office, the East Texas oil fields experienced rapid and uncontrolled development. The Railroad Commission of Texas attempted proration, but the courts struck down the plan. Because of the chaotic situation, Sterling declared martial law in four counties for six months. National Guard troops were sent to the oil fields to limit waste and control production. This action was later declared unwarranted by the federal district court and the U.S. Supreme Court, and the Railroad Commission's plan for proration was accepted. Cotton prices continued to decline during Sterling's term in office.