2018-02-06

Partisan Outcome of Compact Districts

I have often been asked what the likely partisan breakdown of my maps would be. I never had the data to do that analysis, but FiveThirtyEight got the data and analyzed my maps and 7 other plans for various notions of gerrymandered and fair.
In short, my compact maps are very slightly less Republican and a bit more competitive. I've always believed that on average in the last two districtings Republicans have done more of the gerrymandering and stolen more US House seats than the Democrats have. The difference was smaller than I expected though. The difference is probably smaller than this model can usefully tell us about. All models are wrong, some models are useful, and this model is certainly not destiny but can maybe tell us something useful about the biases in the system.
FiveThirtyEight estimates that the current map has 195 safe Republican seats, 168 safe Democratic seats, and 72 competitive seats; and that this will on average elect 234.4 Republicans and 200.6 Democrats. Actually in 2016 we got 241 Republicans and 194 Democrats. 7 seats out of 435, 1.6% off, not bad.
They estimate that under my compact map that goes to 180 safe Republican seats (-15), 151 safe Democratic seats (-17), and 104 competitive seats (+32); with an expected outcome of 232.2 R and 202.8 D (D +2.2).
That 2.2 seat change looks pretty small, but I want to be optimistic about the 32 additional competitive districts. The US may be self-sorting, but while gerrymandering deliberately creates uncompetitive districts on both sides, simply not gerrymandering creates additional competitive districts. I'm not in favor of distorting districts specifically to create competitive districts (which 538 explored and created a whopping 242 competitive districts) but not deliberately creating uncompetitive districts is something I'm solidly behind. Uncompetitive districts make democracy depressing when you know you don't really have any choice, and I want this country to have more democracy.

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