Ian Millhiser:Why Americans Actually Voted for a Democratic House

Based on ThinkProgress’ review of all ballots counted so far, 53,952,240 votes were cast for a Democratic candidate for the House and only 53,402,643 were cast for a Republican — meaning that Democratic votes exceed Republican votes by more than half a million.

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The actual partisan breakdown of the 113th Congress will be very different, however. Currently, Republicans enjoy a 233-192 advantage over Democrats, with 10 seats remaining undecided. That means that, in a year when Republicans earned less than half the popular vote, they will control a little under 54 percent of the House even if Democrats run the table on the undecided seats.

There is a simple explanation for how this happened: Republicans won several key state legislatures and governors’ mansions in the election cycle before redistricting, and they gerrymandered those states within an inch of their lives. President Obama won Pennsylvania by more than 5 points, but Democrats carried only 5 of the state’s 18 congressional seats:

Similar stories played out elsewhere. Obama won Virginia, and Democrats took 3 of 11 House seats. Obama won Ohio, but Democrats carried only 4 of 16 seats in Ohio’s House delegation.