The legislative research office put together this map of Nebraska by county showing the percent voter turnout for the primary election on May 12. Seven out of the top 10 counties with the highest voter turnout in the Nebraska’s 2026 primary election were mail-in-ballot counties. Throughout the state, there are 11 counties that vote through mail-in-ballots only. For Dist 24 - Polk county had the highest turnout at 43.54%