Existing research suggests that to the extent that accountability for congressional performance occurs, it does so primarily through a referendum on the performance of the majority party. If true, this means that the minority party has no incentive to act responsibly, and may even have an incentive to polarize and obstruct. I argue that Americans do not simply hold one summary evaluation of congressional performance. Instead, partisan polarization in Congress has allowed Americans to form distinct evaluations of each congressional party. When casting ballots in House elections, Americans take into account their evaluations of both congressional parties. As a result, American politics is now closer to the "responsible two-party system" ideal set by the American Political Science Association more than six decades ago.In 2009, as House Republican leaders prepared for the start of the 111th Congress, they privately decided their party should "show united and unyielding opposition" to the economic agenda of President Obama and the Democratic congressional majority. 1 The reasons for this decision were not policy oriented, but rather explicitly electoral: a PowerPoint prepared by the House leadership stated that while the purpose of the majority is to govern, "the purpose of the minority is to