Is our increasingly polarized Congress out of touch with the voters who got them into office? Or does it mean that voters themselves are becoming increasingly ideological? Peter Orszag points to evidence suggesting that it’s the latter: There’s research showing that polarization in state-level governments increased even more rapidly than in Congress, at the same time that Republican and Democrat voters were “sorting” themselves into increasingly homogeneous neighborhoods. Political polarization, in other words, isn’t just a Beltway phenomenon, and an increasingly divided electorate may be a big factor.

That said, trying to create more ideologically mixed districts— whether through redistricting or otherwise—could actually make polarization worse, argues Princeton’s Nolan McCarthy. He points out that big ideological differences on the local level — within a small geographic area — are heavily linked to polarized state politics. According to his research, state legislatures with more districts that are ideologically heterogeneous tend to be more polarized. As a result, “attempts to offset geographic sorting by creating heterogeneous ‘strange bedfellows’ districts will likely backfire.”

(Nolan McCarthy)