Why are the Democrats underrepresented in the House? It’s (mostly) the geography, stupid!

The 2012 election gave progressives much to cheer about. In practically every high-profile race where the outcome was at all in doubt,the more progressive candidate won — from the presidency on down. It was the single most satisfying election I have ever experienced in my life. I couldn’t believe it! I kept waiting for something important to go amiss — for Elizabeth Warren to lose, for example, or Tammy Baldwin. But no — all the candidates I most cared about won — a first, in my political lifetime. The cherry on top of the sundae was the right’s post-election, full-scale meltdown. Even now, a full 11 days after the election, they’re forming a circular firing squad and undergoing a nasty recriminations fiesta. Hey, I thought only Democrats did that! Like so many things in politics, it won’t last, but right now it’s a whole lot of fun to be a Democrat.

But as much of a triumph as election 2012 was for progressives, there were some clouds on the horizon as well. Undoubtedly the biggest of these is that the House of Representatives remains comfortably in Republican hands, which means that most progressive pieces of legislation will be thwarted for the foreseeable future. And sadly, according to Nate Silver, the Democrats are unlikely to regain the House in 2014. What is particularly frustrating about last week’s election is that House Democrats apparently won only 46% of House seats, in spite of garnering 50.5% of major party votes. Why did this happen, and what we can do to ensure that Democrats win representation in the House at levels that are equivalent to the votes they receive in the general population?

Political scientists say that there are three main reasons the G.O.P. is overrepresented in Congress, as compared to their national vote share. One reason is the power of incumbency. As political scientist Eric McGhee wrote about the 2010 election:

Congressional elections are not written on a clean slate. Instead, a substantial number of voters give their incumbent the benefit of the doubt unless offered ample reason to do otherwise. That means the party with more incumbents is going to do better, especially in a status quo election with no signs of a broader partisan tide.

Incumbents tend to be better funded and have higher name recognition than their opponents. And they can leverage the considerable power of their office to produce benefits for their district, which tends to win them endorsements and votes.

Incumbency, however, only explains part of it. Partisan redistricting — otherwise known as gerrymandering — also plays a role. Republicans certainly have not been shy about blatant attempts at gerrymandering (remember this?) and political scientists say that partisan redistricting does have an impact. 2010 was a very good year for Republicans, and since in that election so many statehouses remained in or shifted to the GOP column, lawmakers in those states were well-positioned to carve out GOP-friendly districts in the redistricting process that occurred following the 2010 census. Political scientist Nicholas Goedert recently found that

In every state districted by Republicans, Democrats won fewer seats than their historical expectation, and in six cases they underperformed by 20% or more (as a percentage of total seats up for election). So it appears that Republicans gained benefits across the board from controlling the redistricting process.

Even so, the impact of gerrymandering is, surprisingly, smaller than you may think. Says McGhee:

The point should be clear: even under the most generous assumptions, redistricting explains less than half the gap between vote share and seat share this election cycle.

Goedert notes that, according to his findings:

we still observe bias even where we should expect none in the redistricting process. . . [Snip] . . . Democrats also fell short in several states with bipartisan or court-drawn maps, winning on average 7% fewer seats than expected.

Clearly then, something else is going on. What is it? According to Goedert, the most important factor is the geographic distribution of the two parties. Republicans tend to be concentrated in rural areas, Democrats in urban areas, and rural areas are awarded more seats, on a per person basis than urban areas. For example:

[S]tates that are heavily urbanized (such as New Jersey and Pennsylvania) are more distorted against Democrats than more rural states (such as Minnesota and Wisconsin). Indeed, urbanization has a negative and significant effect on the difference between seats won by Democrats and expected seats, even after controlling for the party in control of redistricting.

Another study, by Jowei Chen and Jonathan Rodden, comes to a similar conclusion:

We show that in many states, Democrats are inefficiently concentrated in large cities and smaller industrial agglomerations such that they can expect to win fewer than 50 percent of the seats when they win 50 percent of the votes. To measure this “unintentional gerrymandering,” we use automated districting simulations based on precinct-level 2000 presidential election results in several states. Our results illustrate a strong relationship between the geographic concentration of Democratic voters and electoral bias favoring Republicans.

A more equitable redistricting process would help Democrats gain more seats, but given our country’s skewed population distribution, they would still be facing uphill struggle. But even though Democrats are likely to continue to be underrepresented in Congress, relative to vote share, they are not, says Goedert, “doomed to the the minority for the foreseeable future, or even the next decade. For example:

The Pennsylvania map includes five Republican seats won by Obama in 2008, suggesting that a wave of sufficient strength could reverse the delegation’s majority. But because of unequal concentrations of vote share in most states, not just those with Republican gerrymanders, a Democratic majority will be more difficult than it should be. And this difficulty persists even when both parties agree to the maps.

He concludes, “Changing our redistricting institutions alone will not assure national proportionality.”

UPDATE: To clarify, even automated redistricting simulations, like the ones used here , tend to produce results in which Republicans are overrepresented. This is because, so long as you use traditional geographical criteria for redistricting, it’s very hard to draw up districts in which sparsely populated, Republican-friendly areas do not end up getting more representation than densely populated, Democratic ones. Non-geographic criteria that would create a more level playing field could be used, I supposed, but I don’t know of anyone suggesting such. Ending Republican gerrymandering would help, and should be strongly supported, but even so, Democrats would face an uphill struggle.

Kathleen Geier

Kathleen Geier is a writer and public policy researcher who lives in Chicago. She blogs at Inequality Matters. Find her on Twitter: @Kathy_Gee