Civic Engagement - Voter participation rate (2016) To resort data: click column headings. To download data: click here. County Name Voters by population Rank Voters by population Camas 1 74 Custer 2 73 Bear Lake 3 70 Adams 4 69 Oneida 5 68 Butte 6 68 Lemhi 7 66 Blaine 8 66 Idaho 9 66 Boise 10 66 Teton 11 64 Jefferson 12 64 Valley 13 64 Bonner 14 63 Franklin 15 63 Caribou 16 63 Gem 17 62 Fremont 18 61 Benewah 19 61 Ada 20 60 Boundary 21 60 Latah 22 59 Washington 23 59 Bonneville 24 58 Kootenai 25 57 Madison 26 57 Nez Perce 27 56 Lewis 28 56 Bannock 29 55 Bingham 30 55 Clearwater 31 54 Power 32 54 Shoshone 33 53 Payette 34 53 Cassia 35 52 Twin Falls 36 51 Canyon 37 50 Lincoln 38 49 Gooding 39 48 Owyhee 40 48 Minidoka 41 48 Clark 42 47 Elmore 43 45 Jerome 44 44 Source: 2010-2018: Idaho Secretary of State, (https://sos.idaho.gov/elect/results/history.html); U.S. and State data 2010-2018: United States Elections Project, (http://www.electproject.org/home/voter-turnout/voter-turnout-data);