South Dakota voter registration data

This repository contains county-level voter registration data for South Dakota, broken down by party.

Updated December 9, 2024

The data -- 163 snapshots in time -- comes from the South Dakota Secretary of State's website:

• December 2015 to present: Monthly snapshots, plus election totals
• June 1976 to November 2014 (source 1, source 2): Election totals, typically less detailed than current data

Here's a spreadsheet with a complete list of sources. I use pdfplumber to parse the monthly reports.

Files are named after the snapshot date in YYYY-MM-DD.* format. Individual CSV files live in the data folder. The original PDFs, some of them rendered from web pages, live in the pdfs folder.

The build_files.py script creates two (tidy) combined files, each with two new columns -- county_fips, derived from looking up county names in the us-county-fips.csv file, and election, which lists the type of election for that snapshot date, if applicable, sourced from a file I created, elex-lookup.json:

• sd-voter-registration-data.csv: The columns in this file are date,county,county_fips,party,voters,election -- note that inactive is sometimes the "party" name, so if your goal is to analyze active voter registration, you'd need to filter these out first.
• sd-voter-registration-data-simplified.csv: Same as above, except:
  • All non-Republican/Democratic party categories are collapsed into a single "other" category
  • Inactive records are removed
  • Two snapshot records for Washabaugh County, which merged with Jackson County in 1983, are removed
  • Records for Shannon County, which was renamed Oglala Lakota County in 2015, are renamed with the current county name and given the associated FIPS code