Kyle Kondik observes that “rural/urban divide in American presidential politics is pronounced”
Generally speaking, Republicans win the districts that are geographically large, and Democrats win the districts that are geographically small. This squares with the national political scene — as we noted right after the election last year, Obama won more than 90% of the nation’s 50 most populous counties, while Romney won more than 90% of the counties in rural Appalachia.
This helps explain the Republicans’ structural advantage in the House. Yes, redistricting in many states has something to do with it (although Democrats benefit from gerrymandering in some places too), but Democratic voters are also clustered closer together than Republican voters are, which hurts Democrats. For instance, Obama won 70% or more of the vote in 61 House districts in 2012, while Romney got 70% or more in just 19 districts. Political scientists Jowei Chen of the University of Michigan and Jonathan Rodden of Stanford University argue that the close proximity of Democratic voters dilutes their power in the House: “In many states, Democrats are inefficiently concentrated in large cities and smaller industrial agglomerations such that they can expect to win fewer than 50 percent of the seats when they win 50 percent of the votes,” they wrote.
This clustering becomes readily apparent with just a cursory glance at a map of House results. Based on U.S. census data, the 234 Republican House members represent districts that cover four-fifths (80%) of the United States’ land mass, while the 201 Democrats in the House hold just about 20% of the country’s land.
The Dish 