California provides an instructive case study for the limitations of redistricting reform and the benefits of other more-ambitious changes tackling the demand side of elections. The state drew outsized attention for its nonpartisan commission dramatically redrawing its 53 congressional districts, but it was another lesser-publicized election reform — the top-two primary system — that made the state’s delegation friendlier to moderates. The redrawing of district lines increased political competition in the state, but guaranteeing the top two finishers moved on to the general election regardless of party changed the type of members elected.

In some overwhelmingly Republican and Democratic districts, the top two finishers were from the same party, making the minority party’s voters the crucial swing bloc. That created the spectacle of uber-liberal candidates appealing to tea-party conservatives while archconservatives were finding their inner progressives. One of the most liberal members of Congress, former California Rep. Pete Stark, faced a general-election matchup against fellow Democrat Eric Swalwell, the Alameda County deputy district attorney. Stark was endorsed by President Obama, Democratic elected officials, and organized labor. Attacking the congressman’s temperament, Swalwell appealed to moderates and the handful of Republicans in the district — and knocked off the 20-term member of Congress by a 4 percentage-point margin.

In the conservative, newly drawn 8th Congressional District, the pragmatic Republican whose campaign focused on local issues, Paul Cook, comfortably defeated tea-party-backed challenger Gregg Imus, even though he finished second during the primary. In a matchup pitting two Democratic incumbents against each other, Rep. Brad Sherman claimed tea-party-friendly elements of his voting record while Rep. Howard Berman touted endorsements from more Republican members of Congress.