I don’t have a particularly strong take on how the death of Ruth Bader Ginsburg will affect either the presidential election or the race for control of the U.S. Senate. And I’d encourage you to avoid putting too much stock in anybody else’s take for now, too. The very earliest indication is that President Trump’s desire to move full-speed ahead toward naming Ginsburg’s replacement could be unpopular, but that’s based on only one poll.

But here’s what I do know: the Senate is an enormous problem for Democrats given the current political coalitions, in which Democrats are dominant in cities while Republicans triumph in rural areas. And because the Senate is responsible for confirming Supreme Court picks, that means the Supreme Court is a huge problem for Democrats too. Sure, Democrats might win back the Senate this year — indeed, they were slight favorites to do so before the Ginsburg news. But in the long run, they’re likely to lose it more often than not.

You can probably grasp intuitively that a legislative body which provides as much representation to Wyoming (population: 580,000) as California (population: 39.5 million) will tend to favor rural areas. But it’s a bigger effect than you might realize, so let’s run some numbers. At FiveThirtyEight, our favorite way to distinguish between urban and rural areas is based on using census tracts to estimate how many people live within a 5-mile radius of you. Based on this, we can break every person in the country down into four buckets:

  • Rural: Less than 25,000 people live within a 5-mile radius of you;
  • Exurban or small town: Between 25,000 and 100,000 people within a 5-mile radius;
  • Suburban or small city: Between 100,000 and 250,000 people within a 5-mile radius;
  • Urban core or large city: More than 250,000 people within a 5-mile radius.

As it happens, the overall U.S. population (including Washington D.C. and Puerto Rico) is split almost exactly evenly between these buckets: 25 percent rural, 23 percent exurban/small town, 27 percent suburban/small city, and 25 percent urban core/large city.

But what does representation look like in the Senate? Since each state has the same number of senators, this is simple to calculate. We can take the urban/rural breakdown for each state and average the 50 states together, as in the table below:

The Senate has a major skew towards rural voters

Proportion of population by area across the U.S. as a whole, in each individual state and in the average state (i.e. as reflected in the Senate)

STATERURALEXURBAN /SMALL TOWNSUBURBAN /SMALL CITYURBAN CORE /BIG CITY
STATERURALEXURBAN /SMALL TOWNSUBURBAN /SMALL CITYURBAN CORE /BIG CITY
U.S. population total*25%23%27%25%
Average state35262514
Alaska53%18%28%0%
Alabama5133160
Arkansas583660
Arizona17192935
California8132654
Colorado21183031
Connecticut8354511
Delaware2427490
Florida13273526
Georgia3129327
Hawaii23223519
Iowa5229190
Idaho4236220
Illinois19152838
Indiana3727332
Kansas4125313
Kentucky5220235
Louisiana4130209
Massachusetts6323527
Maryland13222936
Maine692560
Michigan30232819
Minnesota36192520
Missouri4119319
Mississippi652960
Montana594110
North Carolina3736251
North Dakota4939120
Nebraska3617398
New Hampshire3942180
New Jersey5183344
New Mexico4128265
Nevada1392553
New York14141557
Ohio26293312
Oklahoma4423321
Oregon29212426
Pennsylvania23312521
Rhode Island8312239
South Carolina4041180
South Dakota6519160
Tennessee4131280
Texas21173427
Utah21194119
Virginia28223417
Vermont792100
Washington20223919
Wisconsin41271913
West Virginia643600
Wyoming663400

*Totals for the U.S. as a whole include Washington, D.C. and Puerto Rico

Because there are a lot of largely rural, low-population states, the average state — which reflects the composition of the Senate — has 35 percent of its population in rural areas and only 14 percent in urban core areas, even though the country as a whole — including dense, high-population states like New York, Texas and California — has about 25 percent of the population in each group. That’s a pretty serious skew. It means that the Senate, de facto, has two or three times as much rural representation as urban core representation … even though there are actually about an equal number of voters in each bucket nationwide.

And of course, this has all sorts of other downstream consequences. Since rural areas tend to be whiter, it means the Senate represents a whiter population, too. In the U.S. as a whole, 60 percent of the population is non-Hispanic white and 40 percent of the population is nonwhite.1 But in the average state, 68 percent of people are white and 32 percent are nonwhite. It’s almost as if the Senate has turned the clock back by 20 years as far as the racial demographics of the country goes. (In 2000, around 69 percent of the U.S. population consisted of non-Hispanic whites.)

It also means that the median states — the ones that would be decisive in the event of a 50-50 tie in the Senate — are considerably redder than the country as a whole. In the next table, I’ve arranged the states from top to bottom based on how much more or less Republican they were than the national average in the presidential elections in 2016 and 2012.2

A red state is most likely to decide the Senate

Republican margin or deficit in the last two presidential elections relative to national average by state and a blended average (representing current partisan lean)

RANKSTATE20162012BLENDED*
1Wyoming+48.4+44.7+47.5
2West Virginia+43.8+30.5+40.5
3Oklahoma+38.5+37.4+38.2
4Idaho+33.9+35.5+34.3
5North Dakota+37.8+23.5+34.2
6Kentucky+31.9+26.5+30.6
7South Dakota+31.9+21.9+29.4
8Alabama+29.8+26.0+28.9
9Arkansas+29.0+27.5+28.6
10Utah+20.0+51.7+27.9
11Tennessee+28.1+24.2+27.1
12Nebraska+27.1+25.6+26.8
13Kansas+22.5+25.4+23.2
14Louisiana+21.7+21.1+21.6
15Montana+22.3+17.5+21.1
16Indiana+21.1+14.1+19.3
17Mississippi+19.9+15.4+18.8
18Missouri+20.6+13.2+18.8
19Alaska+16.8+17.8+17.1
20South Carolina+16.4+14.3+15.9
21Texas+11.1+19.6+13.2
22Georgia+7.2+11.7+8.3
23Iowa+11.5-2.0+8.1
24Ohio+10.2+0.9+7.8
25Arizona+5.6+12.9+7.4
 MEDIAN  +6.6
26North Carolina+5.7+5.9+5.8
27Florida+3.3+3.0+3.2
28Pennsylvania+2.8-1.5+1.7
29Wisconsin+2.9-3.1+1.4
30New Hampshire+1.7-1.7+0.9
31Michigan+2.3-5.6+0.3
32Minnesota+0.6-3.8-0.5
33Nevada-0.3-2.8-1.0
34Virginia-3.2-0.0-2.4
35Colorado-2.8-1.5-2.5
36Maine-0.9-11.4-3.5
37New Mexico-6.1-6.3-6.2
38Oregon-8.9-8.2-8.7
39Delaware-9.3-14.8-10.7
40Connecticut-11.5-13.5-12.0
41New Jersey-11.9-13.9-12.4
42Washington-13.6-10.9-12.9
43Illinois-14.8-13.0-14.3
44Rhode Island-13.4-23.6-16.0
45New York-20.4-24.3-21.4
46Massachusetts-25.1-19.3-23.7
47Maryland-24.3-22.2-23.8
48California-27.9-19.2-25.7
49Vermont-24.3-31.7-26.2
50Hawaii-30.1-38.8-32.3

* Based on a combination of 75 percent 2016 and 25 percent 2012. This is a simplified version of how FiveThirtyEight’s partisan lean index is calculated.

The median falls in between Arizona and North Carolina, which are, on average, 6.6 percentage points more Republican than the country as a whole. Democrats can compete in these states and are doing so this year, but they’re doing so in an overall political environment which leans Democratic by 6 to 7 percentage points based on the generic congressional ballot and national polls of the presidential race.

In a strong national environment for Democrats, in other words, the Senate can be competitive. Generally speaking, at least. A Democratic-leaning environment wasn’t enough to overcome the Senate’s baseline GOP-lean and a bad map in 2018. Democrats lost seats. And in an average year — and certainly in a year like 2014 where Republicans have the advantage — Democrats face dire prospects in the Senate.

Indeed, despite their current 47-53 deficit in the Senate, Democratic senators actually represent slightly more people than Republicans. If you divide the U.S. population by which party represents it in the Senate — splitting credit 50-50 in the case of states such as Ohio that have one senator from each party — you wind up with 167 million Americans represented by Democratic senators and 160 million by Republicans.

Could the emerging electoral map — with states such as TexasArizona and Georgia becoming more purple — help Democrats in the Senate? Actually, while the shifting politics in those states could massively affect the Electoral College, they don’t help Democrats in the Senate that much because they still have only two senators each.3

Rather, what Democrats really need to negate their disadvantage in the Senate is to find some small-population states that move toward them. Other than Nevada, they haven’t really had any of these recently. (Montana and Alaska are probably the least-implausible candidates, although Montana’s presidential voting has actually been getting redder.) There’s also the chance that the small, predominantly white working-class states of New England — such as Maine, New Hampshire and even Rhode Island — could move against Democrats, which could make their Senate problems even worse, although Maine is polling strongly for Joe Biden this year.

Democrats could also consider adding states to the union. If both Washington D.C. and Puerto Rico became solidly Democratic states (not necessarily a safe assumption in the case of Puerto Rico), the Senate’s Republican lean would be reduced from 6.6 points to 4.5 points. If D.C. and Puerto Rico joined and California were split into three states that ranged from Democratic-leaning to solidly blue, it would deplete further to 2.5 points. But that also goes to show you how robust the Republicans’ advantage is. You could add four Democartic states (D.C., Puerto Rico, California/A and California/B) and the Senate would still have a slight Republican tilt.

Obviously, political coalitions can change over time. Maybe you’re reading this article in 2036 and it seems incredibly silly because Mormons have become a super Democratic group and Montana, Utah and Idaho are all blue states … who knows. But for the time being, the Senate is effectively 6 to 7 percentage points redder than the country as a whole, which means that Democrats are likely to win it only in the event of a near-landslide in their favor nationally. That’s likely to make the Republican majority on the Supreme Court pretty durable.