NY TIMES NATE SILVER
President Obama won the Electoral College fairly decisively last year despite a margin of just 3.8 percentage points in the national popular vote. In fact, Mr. Obama would probably have won the Electoral College even if the popular vote had slightly favored Mitt Romney. The “tipping-point state” in the election — the one that provided Mr. Obama with his decisive 270th electoral vote — was Colorado, which Mr. Obama won by 5.4 percentage points. If all states had shifted toward Mr. Romney by 5.3 percentage points, Mr. Obama would still have won Colorado and therefore the Electoral College — despite losing the national popular vote by 1.5 points.
Contrast this Democratic advantage in the Electoral College with the Republican advantage in the House of Representatives. Democrats actually won slightly more votes in the House elections last year (about 59.5 million votes to the G.O.P.’s 58 million). Nevertheless, Republicans maintained a 234-201 majority in the House, losing only eight seats.
Democrats are quick to attribute the Republican advantage in the House to gerrymandering. This is certainly a part of the story. Republicans benefited from having an extremely strong election in 2010, giving them control of the redistricting process in many states. (Although Democrats were no less aggressive about creating gerrymandered districts in states like Illinois.)
However, much or most of the Republican advantage in the House results from geography rather than deliberate attempts to gerrymander districts. Liberals tend to cluster in dense urban centers, creating districts in which Democrats might earn as much as 80 or 90 percent of the vote. In contrast, even the most conservative districts in the country tend not to give more than about 70 or 75 percent of their vote to Republicans. This means that Democrats have more wasted votes in the cities than Republicans do in the countryside, depriving Democrats of votes at the margin in swing districts. Eliminating partisan gerrymandering would reduce the G.O.P.’s advantage in the House but not eliminate it.
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