Political geography without the Great Migration

[Karpatsky]

Very rough calculations done for fun, by 'resetting' African-American population distribution to 1860 levels. A few simplifying caveats: I didn't account for population changes changing EVs, assumed that all AAs vote Democratic, and that AAs turned out at the same level as the general population. I hope to do a more precise version sometime in the future.

In all these maps, 30% = closer than 5%, 40% = closer than 10%.

2008:

375/163

Closest states:

PA: R+0.47%
NJ: D+1.11%
MO: R+1.63%
MI: D+2.23%
MT: R+2.93%

2012:

353/200

Closest states:

DE: R+0.32%
WI: D+0.87%
CO: D+1.08%
IL: D+1.99%
TX: D+2.30%

2016:

303/235

Closest states:

MS: R+0.13%
NJ: R+0.47%
CO: D+0.63%
NH: R+0.85%
ME: D+2.19%
EDIT:

Here's the data for 2020:



340/198

Closest states:

DE: D+0.02%
MS: D+1.16%
NJ: D+1.47%
IL: D+2.11%
MN: D+2.55

Flips from '16: MS, MN, NJ, DE, NH

Here's my PVI calculation, based only on 2012 and 2016. Sorry to pagestretch, but I couldn't figure out how to do spoilers.

 Wyoming: R+26
 Oklahoma: R+24
 Utah: R+21
 West Virginia: R+21
 Idaho: R+19
 North Dakota: R+17
 Kansas: R+16
 Nebraska: R+16
 South Dakota: R+15
 Indiana: R+14
 Alaska: R+12
 Montana: R+11
 Missouri: R+10
 Arkansas: R+9
 Kentucky: R+9
 Ohio: R+9
 Tennessee: R+9
 Arizona: R+7
 Michigan: R+7
 Pennsylvania: R+6
 Alabama: R+5
 Delaware: R+4
 Iowa: R+4
 Louisiana: R+4
 Nevada: R+4
 Wisconsin: R+3
 Minnesota: R+2
 Colorado: R+1
 New Hampshire: R+1
 New Jersey: R+1
 Illinois: EVEN
 Mississippi: EVEN
 Connecticut: D+1
 Georgia: D+2
 New Mexico: D+2
 Texas: D+2
 Maine: R+3
 Maryland: D+3
 North Carolina: D+3
 New York: D+4
 Oregon: D+4
 Washington: D+5
 Rhode Island: D+6
 South Carolina: D+7
 Virginia: D+7
 Massachusetts: D+8
 California: D+9
 Florida: D+13
 Vermont: D+15
 Hawaii: D+16
 District of Columbia: D+43

EDIT: more done here:

Here's some more. I've stopped counting state EVs because I don't feel like digging up population growth statistics by race at the moment, so these are approximations based on OTL numbers. In no case do I believe they affected the outcome.

2004:

315/223

Closest states:
CT: D+0.02%
LA: D+0.1%
NH: D+0.15%
AR: D+0.48%
NC: R+1.04%

2000:

286/252

My earlier comment on Dem EC advantage was based on the 2012/2016 PVI, and evidently isn't true in general, because Gore gets cheated again in this world, by an even larger margin.

Closest states:
MD: R+0.71%
MS: D+0.78%
GA: D+0.91%
NJ: D+1.38%
NC: R+1.43%


1996:

391/147

Closest states:

MI: R+1.0%
MD: R+1.1%
PA: R+1.6%
AZ: R+1.9%
IL: D+2.6%

Fun fact: under this scenario, a 2% universal swing would give Clinton exactly 450 EVs.

1992:

401/137

Basically nothing changes here re:Perot because he was strongest in the whitest states anyhow.

Closest states:

WI: R+0.1%
NH: D+0.3%
CO: D+1.2%
PA: D+1.3%
CT: R+1.3%

[Karpatsky]

MS was majority black before the Great Migration, so, if no blacks left the South for some reason, it would almost certainly have been a Clinton state in 2016.

Of course, this would require some fantastical events that not only keep black voters in place in the South but nonetheless result in the same late-20th and 21st-century political and other events happening (e.g., would Barack Obama have come anywhere near the Presidency if Michelle Robinson [Obama] was born, grew up and lived in Alabama and they never met as a result?)

You're right - what my model did was directly adjust vote counts by the % difference in population, so what I think happened is black MS turnout was low enough in 2016 such that the greater population was just barely not enough. Clearly this would not be the case were they the majority.

But the purpose of this was not to make a realistic timeline in any way, just to visualize the population movement.

[Karpatsky]

It’s nitpicking, but large numbers of AAs in New York, Massachusetts, and Florida are from the Caribbean, not the U.S. South.

Also fair. I don't know how I would isolate them though. Besides, the only state where I imagine those populations would make a difference is NJ.

[Karpatsky]

Great work! One question, however:

Changes to population numbers would also change the number of electoral college votes for some states. Is there any way to estimate the effect this would have on these maps?

Yeah, I just didn't from the start. This is what I get just by changing the state populations by the proportional % of black population difference:

Which is about what you'd expect, minus KY, which appears to be a marginal case. I didn't check, but I don't think this changes any of the above results.

[Karpatsky]

Here's the data for 2020:



340/198

Closest states:

DE: D+0.02%
MS: D+1.16%
NJ: D+1.47%
IL: D+2.11%
MN: D+2.55

Flips from '16: MS, MN, NJ, DE, NH

[Karpatsky]

Why is MS so close?  Wasn't it solidly majority black before the migration?

It was. I think that's an artifact of lower AA turnout in reality, which likely wouldn't be the case in this alternate world.