Harris County Elections - University of Houston
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Harris County — the largest county in Texas and the third largest in the nation — has experienced substantial changes in its electoral landscape during the 21st century. Once a Republican stronghold, Harris County today leans reliably Democratic. In order to clearly see the changes precinct-by-precinct, the Hobby School has compiled the data for a typical down-ballot judicial race in every November General Election since 2000 (11 total elections), the two-party presidential vote from 2000 to 2020, and the 2018 U.S. Senate race (7 total elections). The precincts have been harmonized across the 20-year period to reflect the 2020 boundaries.


How to Use the Visualization

To switch between Presidential/Senate and Down-ballot results, use the blue toggle button. To see the map change over time, click Play – you can click Pause at any time to stop the animation to see the results of a specific election. If you want to zoom into a specific precinct, enter the precinct number into the search box and click "Enter" and you'll fly to that precinct. Finally, hover over the precinct to get more information on the partisan split and raw vote numbers in that year/race.