When states redraw their political districts after each decade’s new U.S. census, they make sure each district has the same population. (Legislative and State Board of Education districts can vary a bit from the perfect number; congressional districts are much more exact.) But having each district match the others in population masks big differences that greatly affect politics and elections.
Every district has the same number of people, but not necessarily the same number of adults; the voting-age populations vary considerably. And not all residents are citizens, cutting further into the number of people eligible to vote in each district. For example, Houston’s Senate District 6, which just elected Democrat Sylvia Garcia, has a population of 812,881, a voting-age population (VAP) of 551,137 and a citizen voting-age population (CVAP) of 372,420. In other words, fewer than half of the people who live in SD-6 are eligible to register to vote. (The numbers get smaller still: Only 18,141 people voted in the special election runoff that put Garcia in office.) In East Texas’ Senate District 3, which Robert Nichols, R-Jacksonville, represents, the overall population is 843,567, and the CVAP, at 603,385, accounts for well over half of the total.
This map shows how the CVAP in each congressional, House, Senate and SBOE district, respectively, compares with the average district; positive numbers — green on our maps — have greater-than-average CVAPs, while negative numbers — shown in purple — indicate lower-than-average CVAPs.
The Texas Legislative Council built the district-by-district data from five-year American Community Survey data provided by the U.S. Census Bureau. View/Download the data here.