On July 18, the Kentucky State Board of Elections posted new voter registration data. The percentages: Democratic 50.57%; Republican 40.98%; Libertarian .24%; Green .05%; Constitution .01%; Socialist Workers .003%; Reform .003%; independent and miscellaneous 8.13%.

The November 2016 percentages had been: Democratic 51.23%; Republican 40.47%; Libertarian .23%; Green .05%; Constitution .01%; Socialist Workers .003%; Reform .003%; independent and miscellaneous 8.00%.