In order to address classic questions about democratic representation in countries with winner-take-all electoral districts, it is necessary to understand the distribution of political preferences across districts. Recent formal theory literature has contributed new insights into how parties...

Using new data on roll-call voting of U.S. state legislators and public opinion in their districts, we explain how ideological polarization of voters within districts can lead to legislative polarization. So-called "moderate'' districts that switch hands between parties are often internally...