Turner County is SD GOV bellwether

TurnerCourthouseDuring the primary, this blog identified Beadle and Davison counties as the best bellwethers for a Republican gubernatorial primary. That proved correct; both tracked the final statewide result within 2%.

As this blog seeks to use past to understand the present, one may now ask: What counties have been the “bellwethers” that most closely predict statewide results in general elections for governor?

The ten best counties are:

County 2002 2006 2010 2014 Average
1 Lyman 0.3% 1.1% 0.7% 0.8% 0.7%
2 Turner 0.2% 0.6% 1.2% 1.4% 0.8%
3 Codington 0.9% 3.4% 0.4% 2.5% 1.8%
4 Brookings 0.6% 0.6% 2.1% 4.4% 1.9%
5 Lake 3.9% 1.9% 1.1% 1.1% 2.0%
6 Jackson 2.3% 0.5% 3.2% 2.6% 2.1%
7 Lawrence 2.5% 3.3% 1.7% 1.7% 2.3%
8 Charles Mix 1.6% 4.9% 1.3% 2.3% 2.5%
9 Minnehaha 1.7% 5.1% 2.4% 2.0% 2.8%
10 Deuel 5.4% 0.3% 3.4% 2.3% 2.9%

For each county, the % for each election year is the average amount that the county’s result for the winner differed from the winner’s statewide result. The average is exactly that – simply an average of the four numbers.

As you can see, despite this post’s headline, Lyman County is actually a slightly better bellwether than Turner County in the past four elections. So why did this blog select Turner County as the best bellwether? Lyman County is immediately to the north of Billie Sutton’s home of Gregory County and both are West River ranching counties along the Missouri River. A regional bias in favor of Sutton seems likely. No such problem exists with Turner County, which has no obvious ties to Noem, Sutton, or their running mates.

Here is a map that shows the averages for all sixty-six counties (lighter color designates a lower score, and therefore a better bellwether):

Screen Shot 2018-11-03 at 3.41.21 PM

Both Turner and Lyman counties have voted for the winning candidate in each of the last four elections; however, that is true of 54 counties. Yankton, Bennett and Marshall counties are 3/4. Roberts, Corson, Day, Ziebach and Dewey counties are 2/4. Clay County is 1/4. Buffalo, Todd and Oglala Lakota Counties are 0/4. Of course, the last four gubernatorial elections have been Republican wins, so counties that tend to vote Democratic have a worse track record by this measure.

Finally, here is the average deviation from the winner’s percentage for all sixty-six counties, ranked, continuing the top ten from above. This is the data used to populate the map:

County 2002 2006 2010 2014 Average
1 Lyman 0.3% 1.1% 0.7% 0.8% 0.7%
2 Turner 0.2% 0.6% 1.2% 1.4% 0.8%
3 Codington 0.9% 3.4% 0.4% 2.5% 1.8%
4 Brookings 0.6% 0.6% 2.1% 4.4% 1.9%
5 Lake 3.9% 1.9% 1.1% 1.1% 2.0%
6 Jackson 2.3% 0.5% 3.2% 2.6% 2.1%
7 Lawrence 2.5% 3.3% 1.7% 1.7% 2.3%
8 Charles Mix 1.6% 4.9% 1.3% 2.3% 2.5%
9 Minnehaha 1.7% 5.1% 2.4% 2.0% 2.8%
10 Deuel 5.4% 0.3% 3.4% 2.3% 2.9%
11 Brown 1.8% 2.0% 2.0% 5.7% 2.9%
12 Clark 2.7% 1.8% 3.3% 3.9% 2.9%
13 Sanborn 5.5% 0.8% 3.3% 2.7% 3.1%
14 Grant 4.3% 4.7% 1.1% 2.2% 3.1%
15 Union 3.6% 2.5% 3.3% 3.0% 3.1%
16 Brule 2.3% 5.6% 0.4% 4.4% 3.2%
17 Spink 0.2% 6.7% 5.2% 0.9% 3.3%
18 McCook 2.8% 5.9% 0.9% 3.4% 3.3%
19 Pennington 3.6% 2.6% 5.0% 2.2% 3.3%
20 Miner 3.1% 1.8% 8.2% 0.3% 3.4%
21 Kingsbury 6.8% 2.6% 3.6% 0.5% 3.4%
22 Aurora 6.6% 0.6% 4.4% 2.5% 3.5%
23 Davison 1.8% 3.1% 1.7% 7.6% 3.5%
24 Moody 1.5% 6.5% 5.3% 1.3% 3.7%
25 Yankton 9.7% 2.0% 1.2% 1.8% 3.7%
26 Fall River 2.3% 6.0% 4.5% 2.4% 3.8%
27 Lincoln 3.6% 2.6% 4.5% 5.1% 4.0%
28 Jerauld 5.0% 0.4% 7.3% 4.1% 4.2%
29 Gregory 4.7% 4.8% 2.4% 5.2% 4.3%
30 Bon Homme 5.1% 4.9% 6.2% 1.1% 4.3%
31 Hamlin 5.9% 4.5% 2.7% 4.2% 4.3%
32 Bennett 12.3% 0.7% 1.6% 4.7% 4.8%
33 Custer 8.3% 4.7% 4.4% 3.1% 5.2%
34 Mellette 2.0% 3.4% 7.5% 8.3% 5.3%
35 Beadle 5.0% 10.2% 4.4% 1.6% 5.3%
36 Meade 7.8% 1.9% 7.9% 7.7% 6.3%
37 Perkins 11.0% 4.9% 0.8% 9.7% 6.6%
38 Stanley 8.9% 2.2% 5.3% 10.1% 6.6%
39 Edmunds 7.6% 12.4% 2.0% 4.6% 6.6%
40 Hanson 8.4% 9.6% 6.3% 4.5% 7.2%
41 Butte 6.4% 3.9% 8.7% 11.7% 7.7%
42 Hand 0.8% 13.7% 8.9% 7.9% 7.8%
43 Faulk 9.8% 13.5% 2.2% 9.2% 8.7%
44 Tripp 6.5% 9.6% 8.0% 11.2% 8.8%
45 Hutchinson 7.9% 14.5% 4.4% 9.5% 9.1%
46 Walworth 9.5% 12.2% 10.2% 7.4% 9.8%
47 Hyde 11.5% 14.9% 5.9% 8.9% 10.3%
48 Marshall 6.3% 1.0% 9.0% 27.5% 10.9%
49 Corson 14.0% 2.4% 11.6% 16.6% 11.2%
50 Roberts 12.8% 5.5% 12.9% 15.1% 11.6%
51 Hughes 16.6% 8.1% 11.4% 11.2% 11.8%
52 Potter 13.9% 11.4% 9.9% 12.9% 12.0%
53 Sully 14.7% 12.2% 10.0% 12.4% 12.3%
54 Day 10.5% 8.1% 13.2% 18.3% 12.5%
55 Harding 26.4% 4.0% 7.8% 14.2% 13.1%
56 Jones 18.1% 10.7% 12.2% 13.6% 13.7%
57 Clay 18.3% 13.4% 11.9% 14.0% 14.4%
58 Ziebach 15.3% 11.6% 17.9% 13.7% 14.6%
59 Campbell 16.5% 17.1% 17.3% 12.4% 15.8%
60 McPherson 20.0% 18.8% 13.9% 11.9% 16.1%
61 Douglas 17.4% 18.9% 14.5% 14.2% 16.3%
62 Haakon 17.4% 14.6% 14.6% 18.8% 16.3%
63 Dewey 20.6% 6.9% 18.9% 21.1% 16.9%
64 Buffalo 33.9% 16.6% 33.8% 29.3% 28.4%
65 Todd 34.7% 19.8% 29.3% 39.9% 30.9%
66 Oglala Lakota 48.1% 34.4% 43.8% 48.5% 43.7%