4 September 2018 — 0652 mdt
Montana voter registration as a percent of population
As of 1 July, Montana’s population numbered approximately 1,060,000. And as of 2 September, 689,265 Montanans were registered to vote. Using mid-August registration totals, and U.S. Census Bureau county population estimates for 1 July 2017 (the latest available), I plotted the percentage of the population registered in each county as a function of that county’s population. There are some interesting variations.
Generally, the highest registration rates are in Montana’s rural, low population counties that lean Republican. Most likely, these counties have older populations and not as many residents under 18 as larger, and in some cases, Democratic leaning, counties. In some counties, such as Deer Lodge, where the state prison is located, there are significant populations of residents who are of voting age but are not legally qualified to vote. The percentage of the population registered also is lower in the counties that most aggressively cull the deadwood from their voter registration rolls.
Prior to the mid-nineteen-nineties, Montana aggressively culled its voter registration rolls, a practice that created the sawtooth pattern for the 1972–1994 period in the graph below. Then policy changed. Voters were no longer so ruthlessly struck from the registration rolls, which grew. Indeed, in 2000, Montana’s roll of registered voters was larger than the voting eligible population. Again, policy changed, and purging became more aggressive, although not as aggressive as during the sawtooth years.
