There’s a pretty obvious reason that white men make up the vast majority of Republicans elected to the House of Representatives in 2018 but only about 4-in-10 Democrats: The Democratic Party has a lot fewer white members than the GOP. Pew Research Center’s data indicate that, in 2017, about 83 percent of the Republican Party was white, compared to 59 percent of the Democratic Party. In fact, the Republican Party is more heavily white now than the Democratic Party was in 1997 — by a fairly wide margin.
Those data about the composition of each party allow us to run an interesting experiment. Which states have a racial composition that’s most like one party or the other? (Below, any non-Hispanic racial group excludes any Hispanic members.) To figure that out, we compare the density of each racial group to the density of each party. The closer the size of each group is to either party, the smaller the bar showing the deviation from that party.
So take Illinois. The state is 62 percent white, 14 percent black, 17 percent Hispanic and 5 percent Asian. That’s a lot closer to the Democrats (59/19/12/3, respectively) than the Republicans (83/2/6/1).
Here’s how each state compares.
The state whose demographics most clearly mirror the GOP is Wyoming, which reliably votes Republican. The states that most closely mirror the Democratic Party are Virginia, which is blue, and North Carolina, which is red.
We can do the same analysis by looking at how race and education within each party (again from Pew) compare to each state.
The state that resembles the distribution of the Republican Party mostly closely is red Missouri. The state that resembles the Democrats most closely is blue New York.
There’s an interesting — and important — reason to consider the figures above.
It is February 2019, less than a year until the Iowa caucuses. As is the norm, Iowa will be the first state to weigh in on the Democratic Party’s presidential nominees next year, according to the primary-tracking website Frontloading HQ. It will be followed, as usual, by New Hampshire (barring some weirdness from New York that the link in the preceding sentence explains).
Why is that important? Because Iowa and New Hampshire have populations that look a lot more like the Republican Party than the Democratic Party. Of the 50 states, Iowa is 39th most like the Democratic Party. New Hampshire is the 44th most like the Democrats. New Hampshire is also the 13th most like the Republican Party in terms of racial composition — and Iowa is the third-most similar to the GOP in the country, following only Wyoming and North Dakota.
In other words, the first two states to weigh in on who should be the Democratic nominee — undoubtedly helping narrow down the field of contenders — are states that are more likely to resemble the GOP racially.
That’s not determinative, of course. Democrats are more like Democrats than Republicans, by definition, and it’s mostly Democrats who are voting in these contests. But in 2016, we saw the importance of racial density in determining the party’s nominee. Sen. Bernie Sanders (I-Vt.), who had less support with black voters than did Hillary Clinton, won his neighboring state New Hampshire by a wide margin and virtually tied Clinton — the dominating front-runner — in Iowa. He was blown out in South Carolina, though, a state that is the 7th most like the Democratic Party in terms of racial composition.
That’s the good news for the party: South Carolina votes fourth. But first candidates have to get through those first two primaries states that are among the least similar to the Democratic Party in terms of racial/educational composition.
It’s worth noting that the composition of the Democratic Party in a state is likely more diverse than the population on the whole. So a state like North Carolina, which mirrors the party well overall, probably has a more diverse Democratic voting base than the party overall.
That said, Iowa is necessarily fairly unrepresentative of the party simply because the density of whites is so high in the state. Moving the first Democratic primary to a state that’s slightly closer to the party’s demographic might not change the results at all. But the 2016 results suggest that racial differences can make a big difference in the nomination’s outcome.