Newt Gingrich embraced this strategy of drawing majority-minority districts for GOP advantage, as did the Bush Administration Justice Department prior to the 1991 redistricting, even as GOP activists like now-Chief Justice John Roberts campaigned against the VRA because they opposed any race-based remedies. The tipping point was the 1994 midterm elections, when the GOP captured the U.S. House of Representatives for the first time in 35 years and Gingrich because speaker. Many experts on both the left and the right, from The Nation's Ari Berman and prominent GOP election lawyer Ben Ginsberg (who spearheaded the 1991 effort to maximize the number of majority-minority districts), attribute the Republican success that year to the drawing of majority-minority districts; indeed, African-American membership in the House reached its highest level ever, at 40.

VRA districts undoubtedly played a role in the GOP takeover, but they were not the only factor, since Republicans made big gains that year in lots of places outside the South. But in the hardscrabble battles of the 50-50 nation, any advantage at all was embraced, and prominent Republicans like Ginsberg and Gingrich became the loudest proponents of drawing majority-minority districts. Many Republicans still promote this strategy today, and it's the only race-based remedy the GOP has supported in the modern era. The party has been more than willing to shelve its ideology when it suited their naked political interests.

So in Shelby County, many Republicans are trying to have their cake and eat it too. They want the Supreme Court to gut Section 5 of the Voting Rights Act, which prevents them from enacting various voter-suppression laws. But they want to preserve the other parts of the VRA that provide the legal impetus for drawing majority-minority districts. One can't help but admire their cleverness.

Meanwhile, it's only going to get worse for the Democrats. Not only has the drawing of majority-minority districts led to fewer elected Democrats, but today single-seat districts themselves have become a huge barrier to Democrats retaking the House. That's because shifting partisan demographics have left Democratic voters more geographically concentrated than Republican voters. The problem is easy to see in urban areas, where Democratic votes are heavily concentrated. Urban Democrat House members -- a large number of whom are minority -- win with huge majorities, but winning a district with 80 percent doesn't help the party gain any more seats than winning with 60 percent. It just bleeds more Democratic voters out of the surrounding districts.

Yet it's not just urban districts that reflect the tilted partisan landscape. Election simulations have shown that partisan demographics -- even more than the gerrymandering of district lines -- give the GOP a natural, built-in edge in a majority of House districts. Those simulations predict that in 2014 the GOP will maintain control of the House even if Democrats win the nationwide House vote by nearly 10 percentage points. This dynamic was illustrated in the 2012 election, when President Obama defeated Mitt Romney by nearly five million votes nationwide, but Romney's vote was more efficiently dispersed -- he won 226 House districts to Obama's 209. That means Democrats can win a House majority only if their candidates win numerous districts won by Romney, a steep uphill climb. This explains the oddity of 2012, when the Democrats won the most votes nationwide in House races but still ended up with a minority of seats.