Here at Daily Kos Elections, we live and breathe elections data, and we’ve collected a ton of it (most of which you can find here). But when you want to know more about a specific congressional district, it can be hard to contextualize hundreds of numbers across multiple spreadsheets. We’ve therefore added a new page for each district to our Atlas of the 117th Congress: a snapshot of key data.
Pictured above is the snapshot for Texas’ highly competitive 24th Congressional District, where Democrat Candace Valenzuela is vying to become the first-ever Black Latina to serve in Congress—and flip an open seat long held by Republicans, who are hoping that former Irving Mayor Beth Van Duyne can defend it for them. You can find a full-size version of the snapshot right here, which we’ll walk through one step at a time below.
We start at the top where, besides showing the obviously necessary information of which district we’re talking about, we note the vintage. Our first version is for the districts of the 117th Congress, which will be elected November 2020.
1. Description
The basics: Where is this district? Who represents it?
Here we see our crowdsourced geographic descriptions of each district, and the largest places in it (or neighborhoods for districts in large cities).
There’s also a map showing where the district is in the state from the maps in our Atlas, which includes five files of maps for every congressional district as well as the district snapshot.
The current representative is also shown, or, in cases where no elections have been held since redistricting last took place (such as in North Carolina), the representative of the old district most similar to the new district is shown. Snapshots will be updated with the winners of the 2020 election when the new Congress is sworn in, and when vacancies occur or are filled.
2. Election Results
Our signature data product, presidential election results by congressional district, is highlighted here. The three most recent House election results are included as well.
Points on the left side show a Republican winning; on the right, a Democrat. The line in the middle shows a margin of zero.
Below that, a histogram shows the presidential margins of all congressional districts for context, with the district in question highlighted. The horizontal scale for both charts is the same.
In this case, we see that TX-24 has rapidly moved toward Democrats, with Romney winning by more than 22 points but Trump besting Clinton by barely six points.
3. Demographic Quintiles
The two data points that tell you the most about a district (after election results) are education levels and racial demographics. Daily Kos Elections Contributing Editor David Jarman has found the two together can be especially useful in understanding the changes in congressional district political behavior.
This graph shows the rank of each district—for instance, 41st most-educated district—for both statistics (it does not plot the values—for instance, 47% college educated—themselves). Lines show quintiles; that is, they divide the plot into fifths. The x-axis ranks the share of the population that is non-Hispanic white, with the whitest districts on the right. The y-axis ranks the share of those over the age of 25 who have a bachelor’s degree or higher; the most educated districts are at the top. The actual numbers for both statistics are shown below the graph.
TX-24 is one of the most educated districts in the country; 47% of those over the age of 25 have a college degree. It is in the top quintile for education, near the top of the chart.
It is also more diverse than average on the left side of the chart. A minority of the population is non-Hispanic white, 45%.
Districts with this profile typically elect Democrats, which is why the box that TX-24 is located in is shaded blue. If you click through to Jarman’s piece, you’ll see that Democrats currently hold 23 of 28 districts in the same box as TX-24. This, combined with the rapid movement in election results here we examined above, is part of the reason this seat is a toss-up in 2020.
The shading of the plot reflects the distribution of seats: Districts near the upper left corner are very likely (but not guaranteed) to elect Democrats, while districts in the lower right corner are very likely to elect Republicans.
4. Urbanization
If you’ve been following elections at all in the past few years, chances are you’ve heard a fair amount about suburban voters. In 2018, most of the congressional districts that flipped from Republicans to Democrats were mainly suburban. That’s not to say that’s the only place Democrats made gains; rather, that’s where the gains were able to flip seats.
Which districts, though, actually are suburban? Beyond the I-know-it-when-I-see-it definition, it’s not the easiest thing to sort out. Fortunately we have two new methods to work with that both provide some nuance: first, one that splits districts into three categories based on responses to a Department of Housing and Urban Development (HUD) survey; and second, a method created by our own David Jarman that gives even more granularity with five categories.
The first method is well-suited to show on a ternary plot, seen to the right. A district that is 100% rural would be all the way at the bottom left corner, at the tip of the green part of the triangle. One that is 100% urban would be at the very top of the triangle. And one that is 100% suburban would be in the lower right corner. A district evenly split between all three would be right in the center.
Our district of interest, TX-24, is only 1% rural by this method, so we find it sitting on the far right edge of the triangle. It’s also classified as about three-quarters suburban and one-quarter urban; this means it’s about three-quarters toward the suburban corner on the right side.
David Jarman’s method adds two new categories: exurban for rural-ish areas that are still within commuting distance of a major urban area, and micropolitan for small- to medium-sized towns that aren’t part of a major metropolitan area. These numbers are shown in the chart below the triangle. In this case, TX-24 has a small portion of the population defined as exurban.
5. Economy
This section shows the percentage of the workforce in the district that is employed in each listed industry grouping, and at the bottom, median household income and per capita income.
Each industry has a bar and a circle. The circle represents the data for the district in question; the bar, however, shows the range and distribution of all districts for context. The darkest portion of the bar shows where the median value is, while the color fades into the background at the extreme values.
In our example district, TX-24 has a greater share of workers than is typical in the professional, scientific, management, and administrative category; the finance and insurance, and real estate category; and the transportation and warehousing, and utilities category. It’s on the short side in the education, health care, and social assistance category.
The industry workforce data can be useful for filling in more information on the character of a district. Most people will not be surprised to find a number of Ohio districts with a strong component of manufacturing; Arkansas’ 4th District does too, however, something that is readily apparent with a glance at the Economy section of its snapshot.
6. Identity
This panel combines data from several different census questions about race, ethnicity, ancestry, and nationality.
The chart in the lower left shows the standard race/ethnicity questions. The numbers are for the Latino/Hispanic categories and the non-Hispanic/Latino race alone categories. The colors of the bars are roughly keyed to the map above the chart.
The list in the lower right displays the six most common responses for ancestry or origin using several different census questions together, as described here.
The chart on the right, however, displays every category, each with its own unique shade. The point of this chart is not to be able to identify each slice by color (although with practice that may be possible for the most common groups); rather, it’s to show the diverse origins of the population and especially the diversity within the standard census categories used in the bar chart on the left. Each of the census categories has a range of colors, although the colors do not match perfectly; for example, not all nations of the Caribbean are Spanish-speaking, but they are all colored orange. Note also that the colors of the bar chart do not change no matter the composition of the category. See the full guide to interpreting this chart here.
For TX-24, we see three significant green sectors in the circular chart, all listed in the table below; Irish (darkest green), English (medium green), and German (pale green). There are also some lime green sectors; the largest of these, adjacent to the yellow African American sector, is “American” (a response that about 5% of U.S. residents give to the census to explain their ancestry). We also see a substantial red sector dominated by Mexican origin, but including plenty of smaller segments. And we see a significant selection of purples and blues, with the largest sector being Indian, also listed in the table below.
7. Notes
In the snapshot we include links to this post, our data page, and the Atlas. To the right you can see a preview of the sorts of maps we have in the Atlas. Our data collection has much, much more than we present here or in the Atlas, including statewide election results by state legislative district, special election trackers, open seat data, fundraising numbers, and more.