Best Congress Money Can Buy

It seems like it's not just the executive but also the legislative of the American state that is "but a committee for managing the common affairs of the whole bourgeoisie", as Marx and Engels said in another context. Princeton's Larry M. Bartels on Economic Inequality and Political Representation (via Ezra Klein):

I examine the differential responsiveness of U.S. senators to the preferences of wealthy, middle-class, and poor constituents. My analysis includes broad summary measures of senators’ voting behavior as well as specific votes on the minimum wage, civil rights, government spending, and abortion. In almost every instance, senators appear to be considerably more responsive to the opinions of affluent constituents than to the opinions of middle-class constituents, while the opinions of constituents in the bottom third of the income distribution have no apparent statistical effect on their senators’ roll call votes. Disparities in representation are especially pronounced for Republican senators, who were more than twice as responsive as Democratic senators to the ideological views of affluent constituents. These income-based disparities in representation appear to be unrelated to disparities in turnout and political knowledge and only weakly related to disparities in the extent of constituents’ contact with senators and their staffs.