Let's Gerrymander!

It's been 18 months since Stochastic Democracy wrote about Tobler's Law and its applications for Gerrymandering.

In short: Democrats tend to be clustered together, while Republicans are spread out. This creates a large and natural pro-Republican bias when States try to adopt seemingly 'fair' maps based on aesthetically pleasing, 'compact' districts.

But it seems to be intuitive that in a Democratic system a truly fair redistricting would be one that reflects the will of the voters- one in which the share of districts a party gets closely matches its share of votes.

StochasticDemocracy therefore determined the 'fair' share of Congressional districts Democrats should receive in any state by calculating the Weighted 2010 Congressional Averages by Voting Eligible Population- therefore getting rid of both the impact of illegal immigrants (who get counted in the Census but don't actually get to vote) and under-age residents.

We then apply a universal swing- so that the average Congressional Democrat received 50% of the vote. If the districts were fair, we would expect Democrats to win roughly the same percentage of seats in a state that they win in terms of votes.

We can use this to approximate the 'fair' amount of Democratic, Swing and Republican seats there should be in a state as follows:

The number of safe Democratic seats should be the percentage of votes that Democratic candidates would receive in a neutral national year, minus 5% , multiplied by the number of seats the state has, rounded to the nearest integer.

The number of safe Republican seats should be the percentage of votes that Republican candidates receive in a neutral year, minus 5%, multiplied by the number of seats in the state, rounded to the nearest integer.

The number of swing seats should be the total number of seats minus the sum of Democratic and Republican seats.

Finally, the following table also shows how many seats are expected to elect Democrats under the boundaries of the 112nd Congress, in a neutral year. Keep that in mind when comparing it to the first three columns- the first three columns use the number of seats a state will include in the next decade, the last column uses the number of seats a state was assigned for the last decade.




It turns out that it is possible in most states to create Gerrymanders that follow these rules. In most cases, they are much cleaner than the current lines.

Compare, for instance, the current Maryland map (6-2 Democratic) with our proposed 5-2-1 map.



Even of the some more daunting proposals are possible to draw.
Here, for example, is a wonderful map of New York State by Swing State Project user Johnny Longtorso that creates 8 GOP-leaning and 3 swing districts.


Or, just as interesting, a compact Alabama map by SSP user roguemapper with three districts that were won by Barack Obama in 2008- and that should be easily winnable for Southern Democrats. Of course, this map ignores the VRA requirement for an African-American majority seat. But wouldn't African-Americans in Alabama be better represented in Congress by three Democrats with a majority-Black primary electorate than by just one African-American Representative from a very heavily African-American district?


Granted, in some states it seems impossible to redistrict fairly- those are the states where votes are distributed very evenly throughout the state. It won't be possible, for instance, to carve out a GOP seat in Maine, where John McCain won just one tiny county, or three Republican seats in Massachusetts, where Pres. Obama's weakest county still gave him 53% of the vote. Fair representation being impossible in some states under our current system is, in fact, a troubling sign for our Democracy and should be a rallying cry for Election Reform.

But as long as we operate under the current rules, every effort should be made to ensure fair representation for every voter in the country, Democrat or Republican.