As Swing Districts Dwindle, Can a Divided House Stand? by Nate Silver

...There have been other periods in American history when polarization was high — particularly, from about 1880 through 1920. But it is not clear that there have been other periods when individual members of the House had so little to deter them from highly partisan behavior. 

In the partisan era between 1880 and 1920, there were extremely rapid shifts in the composition of the House. For example, Democrats went from controlling 72 percent of House seats in 1890 to 26 percent in 1894. That is equivalent to Democrats losing about 200 seats in the House relative to today’s baseline of 435 Congressional districts. 

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Certainly, Republicans can’t be entirely happy with their predicament. The Electoral College now seems to disadvantage them at least slightly, and if they struggle in the 2014 and 2016 elections, a better case can be made that the party is underachieving. 

But because of the way districts are configured, their position in the House should be quite robust: it would require a Democratic wave year, and not a merely decent election for Democrats, as in 2012, for Republicans to lose control of the House. 

These strengths and weaknesses for the Republican Party could be self-reinforcing, or at least they may have the same root cause. The district boundaries that give Republicans such strength in the House may also impede the party’s ability to compromise, reducing their ability to appeal to the broader-based coalitions of voters so as to maximize their chances of winning Senate and presidential races. If so, however, that could mean divided government more often than not in the years ahead, with Republicans usually controlling the House while Democrats usually hold the Senate, the presidency, or both. As partisanship continues to increase, a divided government may increasingly mean a dysfunctional one.