Researchers analyzed 180 million voters to map political divides manifest on a neighborhood scale. DFW, pictured above, breaks down as expected.

Politics & Government

New Maps Detail Neighborhoods’ Political Divides

We're used to speaking about blue and red states. New research shows how those divides trickle down to the neighborhood level.

We’re used to talking about red and blue states, and about neighborhood divides centered around income inequality and the lingering legacy of racial segregation. But to what extent do these two things overlap? Do social economic and demographic factors create red and blue neighborhoods? According to a new study by two Harvard researchers, the answers is they do.

Jacob Brown and Ryan Enos sorted information on 180 million U.S. voters and attempted to map their political divisions on a neighborhood scale, publishing the results in Nature. The researchers don’t know, of course, how people voted in the recent election, but they crunched the data by analyzing public data like demographic information, voter registration, and whether voters participated in party primaries. What they found is that the country’s political divides extend into neighborhoods, and, in some case, even manifest on a block-by-block basis.

In some ways, the broad outlines of the maps aren’t anything new. Hand a red and blue crayon to anyone who pays close attention to local politics and ask her to color in the the political affiliations of the neighborhoods, and you might end up with a map like the one of DFW pictured above. But this data drills gets so granular that it manages to quantify some eyebrow-raising results. For example, as  the New York Times reports:

It’s not just that many voters live in neighborhoods with few members of the opposite party; it’s that nearly all American voters live in communities where they are less likely to encounter people with opposing politics than we’d expect. That means, for example, that in a neighborhood where Democrats make up 60 percent of the voters, only 50 percent of a Republican’s nearest neighbors might be Democrats.

Urban democrats are among the least likely to encounter people who don’t agree with their political outlook, but the ideological isolation also exists in small towns, rural communities, and urban areas in predominantly red states.

“Drawn this way, about 25 million voters — urban Democrats especially — live in residential circles where at most only one in 10 encounters is likely to be with someone from the opposite party,” the Times reports. “Democrats in parts of Columbus, Ohio, and Oklahoma City live this way. So do Republicans in the reddest parts of Birmingham, Ala., and Gillette, Wyo.”

Drilling down even deeper into the data, the researchers were able to find that Republican and Democratic voters don’t merely dominate particular census tracts or ZIP code, they tend to cluster together within those geographical distinctions. Does this mean that Americans are choosing their homes based on their neighbors’ politics? Not necessarily so.

The maps don’t suggest a self-sorting as much as they suggest how both parties have evolved politically as the country’s many existing demographic, economic, and socioeconomic divisions widen. “None of these voters have to move to effectively “sort” on a map; rather, their preferences change in place (in ways that may show up in their voting behavior before voters update their party registration),” the Times says.

Flip this study on its head and you could draw the conclusion that these maps aren’t so much showing how neighborhoods break down politically, but rather the widening gulf in how different Americans experience life, which finds expression in the increasingly divergent ideologies of the two dominant political parties. But according to one Harvard political theorist, the data may also reflect some partisan polarization on a neighborhood-scale:

“I do think that something new is happening at the neighborhood level around partisan politics,” said Nancy Rosenblum, a political theorist at Harvard who has written a book about neighbors. Interactions between neighbors have long been distinctly nonpartisan, she said, grounded in values like reciprocity — I’ll lend you my leaf blower, you watch my kid.

But she fears that a more malignant kind of politics is seeping all the way down into neighborhoods: “The most interesting question to ask here is: How deep does it go? And the test for how deep it goes for me is: How do neighbors in neighborhoods behave during disasters?”

We have a lot of recent experience with that last question that offers some anecdotal evidence, at least, about how these divides may — or may not — manifest in a crisis. On the one hand, during the recent winter storm, the response from neighbors appeared to be magnanimous, with neighbors helping neighbors where they could regardless of any apparent political affiliation (even if some well-off Texans opted to simply flee their powerless homes). On the other hand, the likelihood of encountering mask-less people in some DFW neighborhoods rather than others shows one way in which these political divides express themselves during a disaster response. The conclusion to draw from this experience may be that, as long as there isn’t time for disasters to manifest a partisan dimension, neighborhood-level political divides won’t come into play.

But when issues do become partisan, things get more complicated. As the Harvard researcher Ryan Enos told the Times, their research offers a warning. After all, the entrenched overlapping of political and social divides has not played out well in the past.

“We know that with groups in general, when they’re separated, bad things happen,” Mr. Enos said. “That has proved true with racial segregation, and religious and ethnic divides — patterns of separation that make it easier to demonize one another, and harder to share resources or power.

“The question with political parties is whether those are sufficiently like those other groups that we should worry about that happening.”

Read the whole report here.

 

 

Newsletter

Get a weekly recap in your inbox every Sunday of our best stories from the week plus a primer for the days ahead.

Find It

Search our directories for...

Restaurants

Restaurants

Bars

Bars

Events

Events

Attractions

Attractions

View All

View All

Comments