Back in 2013, I wrote about hidden holes when a party engineer wins the counties for himself. This idea comes into force in 2018.
Gerrymandered victories can come back hard, because they often have a mix of Democratic, Republican and most importantly, independent (and manageable) voters. This would explain some of the nearly surprising races in North Carolina and Michigan.
To quantify this, let’s look at the GOP-organized counties in the 3 states that are ranked: NC (CD 2/7/9/13), Michigan (2/6/7/8/11) and Ohio (December 1, 2016) in it poll available. In each of these 12 counties, Trump received more votes than Clinton with an average margin of 11.6%.
Incumbents ran well against Trump, winning their last election in 2016 with an average rate of + 20.7%. But for now, those counties also show an average Republican lead rate of just 2.8% – a difference of 18 points for the Democrats. This is twice as large as the fluctuation in national polls, which have gone Democrats about 9 points.
Here’s a comparison for all counties, with the variation calculated between the 2016 House margin and the current 2018 polls:
|Profit in 2016||Trump-Clinton||Poll in October 2018||Swing the rope towards D|
|NC-07||R + 22.0%||R + 17.7%||D + 4%||26 pts|
|MI-11||R + 12.7%||R + 4.4%||D + 1%||14 pts|
|NC-02||R + 13.4%||R + 9.6%||D + 1%||14 pts|
|NC-09||R + 16.6%||R + 11.6%||Tie||17 pts|
|OH-12||R + 36.7%||R + 11.3%||R + 1%||36 pts|
|MI-08||R + 16.8%||R + 6.7%||R + 3%||14 pts|
|NC-13||R + 12.2%||R + 9.4%||R + 3%||9 points|
|MI-06||R + 22.2%||R + 8.4%||R + 4%||18 pts|
|MI-07||R + 14.9%||R + 19.0%||R + 4%||11 pts|
|MI-02||R + 30.3%||R + 17.6%||R + 6%||23 pts|
|OH-01||R + 19.2%||R + 6.6%||R + 9%||10 points|
|OH-16||R + 30.8%||R + 16.7%||R + 9%||22 pts|
Democrats take the lead in three of these counties – NC-02, NC-07 and MI-11 – and are bound by NC-09.
So the dike risks a little overflow in North Carolina. This is a state where a racist has been demolished and replaced with a map that’s still partisan – but doesn’t use race in the same way. As a result, the gerrymander gave Republicans a slightly narrower margin of safety. Think of it like removing the top sandbag from a dike.
In Ohio and Michigan, party maps seem to be getting better at capturing. However, in 9 out of 12 counties in these three states, ballot rate was within 5 points in both directions. That is cut it pretty close.
Does this mean gerrymandering is unimportant? Nothing. These counties were safe for their incumbents in 2012, 2014, and 2016. 2018 was a sizable volatility by historical standards – larger than the volatility from the prevailing rate of return. George W. Bush in 2004 arrived by Barack Obama in 2008. Of course there is some point in where a gerrymander fails. Always have. That doesn’t change the fact that these counties are designed to be uncompetitive under a wide range of normal political conditions.
PS: Also note that legal actions have been cut off for gerrymanders for several years now. Dave Daley documents Progress is slow and steady.