Can someone make a Missouri map of McCaskill% minus Obama% 2012?

[Franknburger]

@ MilesC56: Is your map displaying the change in absolute percentages, or in two-candidate margins? I did some cross-checking on a randomly selected county (Nodaway in the North-West), where, according to this unofficial source,  McCaskill performed 17% better than Obama ..

In any case, I understand from the map that the Obama-McCaskill gap is primarily a rural white phenomenon, which seems logically, as (a) non-white voters should already have overwhelmingly voted Obama, leaving little potential for such a gap to appear, and (b) the major urban/suburban counties, i.e. St. Louis and Jackson, already went for Obama, which also limits the potential of additional McCaskill gains.

Now, let's take the Nodaway county example, on of the more populated counties in the North-West of the state (pop. 23.370). As per the 2010 census, it was 93.3% non-Latino white, 2.7% black, 1.5% Asian, 1.4% Latino, 1% other, and voted 35.3% Obama in 2012. I haven't done any detailed number crunching, but, assuming the usual gender gap, something like 32% white men and 38% white women in Nodaway voting for Obama looks plausible. If McCaskill had only benefitted from white female votes, her 52.2% would mean something like 72% among white women. Not completely unlikely, but pretty high.
Nodaway is traditionally leaning Democratic on the local & state level, and has since 1996 always voted some 8-20% more Democratic for Governor than for President.  In 2012, the gubernatorial gap was 15.5%, not quite as high as the 17% Obama-McCaskill gap, but also substantial. As such, in Nodaway county it seems to be less a case of Todd Akin having alienated white women (which he surely did, and which is why he underperformed compared to the gubernatorial election), but of national Democrats being unable to tap into an existing white rural voter reservoir that state-level Democrats manage to mobilise. Note that this inability is not Obama-specific, but already applied to Clinton, Gore and Kerry. In 2008, Obama did comparably well  (10% gap, same as for Gore), though his 2012 performance was rather towards the lower end.

Another observation - from a random check of a few of these North-western counties, they seem to have sizable German ancestry (25-30% of population) Not that this really surprises me - it fits into a pattern observed elsewhere, see e.g. this thread:

https://uselectionatlas.org/FORUM/index.php?topic=169054.0

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In addition to Missouri, there have been two more Senate surprises in 2012, namely Indiana and North Dakota. Does anybody happen to have similar "US-Senate D minus Obama" maps for these states at hand?. It would be interesting to check whether they display patterns similar to Missouri.

[Franknburger]

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In addition to Missouri, there have been two more Senate surprises in 2012, namely Indiana and North Dakota. Does anybody happen to have similar "US-Senate D minus Obama" maps for these states at hand?. It would be interesting to check whether they display patterns similar to Missouri.

I made this a while ago:



Feel free to check it

Oh, I trust you, now that I have understood how you come to your numbers . Thanks for the map!

If I see correctly, the biggest margin differentials (>30%) were in the following counties:
Logan (pop. 1.990, 68.5% German ancestry as per 2000 Census)
Emmons (pop. 3.559, 61.8% German ancestry)
Divide (pop. 2.071, 64,7% Norwegian, 24.0% German ancestry)
Pierce (pop. 4.357, 30.3% German, 28.4% Norwegian ancestry)
Sheridan (pop. 1.327, 66,1% German, 16.3% Norwegian)
Eddy (pop. 2385, 47.4% Norwegian, 40,7% German ancestry)

Now, it is pretty difficult to find a rural county in North Dakota that is not full of people with Norwegian and/or German ancestry (there are three of them, which all happen to be dominated by native Indian reservations). As such, we can only conclude that the President-Senate gap is (a) a white rural phenomenon, and (b) occurs across counties with strong German and/or Norwegian ancestry, but is neither necessarily caused  by, nor restricted to these ancestry groups.

Indiana, with its wider variation of ancestries, might be more telling in this respect, but I assume that if you, MilesC56, had a respective map available, you would already have posted it.  

[Franknburger]

The only county that Donnelly overperformed Obama by less than 10% was Lake, even there he did 9.92% better; for the sake of convenience I grouped Lakes in with the >10% counties so I didn't have to add an interval.

Thanks a lot! Pretty interesting and quite specific pattern:

First of all, there are the areas where Obama already had a relatively good showing, meaning there was less potential for Donnelly  gaining on top of him -Marion (Indianapolis), Vigo (Terre Haute). Tippercanoe (Lafayette), the southern Lake Michigan shore, and the Ohio valley. Donnelly's strong showing in his 'old' IN2 congressional district is also not too surprising.

However, different from Missouri and  North Dakota, the Senate-Presidential gap in Indiana appears to be more a suburban / exurban than a rural phenomenon. It was strongest in the Terre Haute periphery (Sullivan / Owen / Knox), and also above average around Lafayette, to the South-East of Indianapolis, around Muncie, and to the North-West of Evansville-[Evansville itself does not fully fit the pattern, probably because it is Richard Mourdoch's political home].

A few areas stand out, and deserve to be discussed in more detail (anybody here with local knowledge?):

First of all, there is Delaware County (Muncie): With some 70,000 city inhabitants (County 117,000), not small-town anymore, but also not the size of a city/ county you would have assumed to be won by Obama (50.3% in 2012). The county is 91% white.  Okay, Muncie is a college town, which changes things a bit. Nevertheless, one would at least assume that Obama already pretty much maxed out the Democratic vote potential, but Donnelly managed to take the county by 56.5%. Moreover, Donnelly also won several of the neighbouring counties such as Blackford (pop. 14,000), Madison (pop. 134,000 seat is Anderson), and Henry (pop. 48,500). Wayne (pop. 71,000) and Fayette (pop. 25,500), a bit further to the South-East, complete the list of Donnelly counties in the area.

Conversely, in Allen County, which houses Fort Wayne, Indiana's second largest city, and is 'only'  83% white, I would have expected Obama to do better than the 40.8% he received in 2012. And Donnelly? 45.3%, 'just' 4.5% more than Obama. In fact, the whole North-East of the State neither put much faith in Obama, nor in Donnelly.

What about ancestry? German Americans are found everywhere across the State (I hadn't realised so far how "German" Indiana is), but in varying shares. The least "German" part (10-20% German ancestry) is the Donnelly cluster around and to the South-East of Muncie (predominantly "American" ancestry), while in the Republican North East, German ancestry shares range between the mid-twenties and the low thirties. And there is another area with substantial German ancestry (around 35%) in the South-East towards Cincinnati that also went strongly for Romney, and where Donnelly only did marginally better than Obama. Issue closed? Well, definitely for the suburban part of the Senate-presidential gap phenomenon.

But there are also a few rural counties in Indiana that happen to have substantial Democratic base support and/or showed a strong Senate-Presidential gap. Aside from Perry county, that has already been discussed extensively elsewhere; neighbouring Dubois (54% German ancestry) and Spencer (33% German ancestry) fall into this category...