On Jan. 3, 2011, then-California Gov. Arnold Schwarzenegger packed up his belongings and left downtown Sacramento’s Hyatt hotel — the governor’s mansion is primarily an historic site for tourists at this late date. Few realized they were witnessing the final chapter of a distinct political species.

At the time, it felt like a temporary setback, a cyclical changing of the guard in a state known for its political eccentricities. But looking across the following decade and a half, a sobering reality sets in: Schwarzenegger wasn’t just a transitional figure — he was the end of the line. For the California Republican Party, the door to the state’s highest executive office has been closed by the slow accumulation of demographic shifts and new political rules.