House Democratic candidates won about 50.5 percent of the national vote in November, but took just 46 percent of the seats. In the last 40 years, only one other time — 1996 — did the party that won the majority of the votes end up with a minority of the House, said Nicholas Goedert, a political science researcher at Washington University in St. Louis in Missouri. Democrats actually gained two seats in the Senate.
Political scientists point to two factors influencing this divergence: a redistricting process dominated by Republican legislatures, and even more so, the concentration of Democratic voters in urban enclaves.
Gerrymandering did matter. In nine states redistricted by Republicans, the Democratic vote share was well above the percentage of seats won, Mr. Goedert said. For instance, in North Carolina, Democratic House candidates won 51 percent of the vote but only 27 percent of the House seats. Where Democrats drew the lines, in Illinois, Maryland and Massachusetts, Democratic House delegations fared better than their vote totals, but not as drastically. This points to an inherent advantage for Republicans. In closely contested years, like 2012, the concentration of Democratic voters in cities has put them at a loss — and given House Republicans little reason to fear national opinion.
Districts really need to be based on population rather than geography if the House is going to be truly representative. There is already a structural representational imbalance in the Senate. We don’t need that in the House as well.