| County | Count |
| Adair | 1 |
| Adams | 0 |
| Allamakee | 0 |
| Appanoose | 0 |
| Audubon | 1 |
| Benton | 0 |
| Black Hawk | 6 |
| Boone | 0 |
| Bremer | 0 |
| Buchanan | 0 |
| Buena Vista | 1 |
| Butler | 0 |
| Calhoun | 0 |
| Carroll | 0 |
| Cass | 0 |
| Cedar | 1 |
| Cerro Gordo | 0 |
| Cherokee | 1 |
| Chickasaw | 0 |
| Clarke | 1 |
| Clay | 0 |
| Clayton | 0 |
| Clinton | 0 |
| Crawford | 0 |
| Dallas | 2 |
| Davis | 0 |
| Decatur | 0 |
| Delaware | 0 |
| Des Moines | 0 |
| Dickinson | 3 |
| Dubuque | 1 |
| Emmet | 0 |
| Fayette | 0 |
| Floyd | 1 |
| Franklin | 0 |
| Fremont | 0 |
| Greene | 1 |
| Grundy | 0 |
| Guthrie | 1 |
| Hamilton | 0 |
| Hancock | 0 |
| Hardin | 1 |
| Harrison | 0 |
| Henry | 0 |
| Howard | 0 |
| Humboldt | 0 |
| Ida | 0 |
| Iowa | 0 |
| Jackson | 1 |
| Jasper | 2 |
| Jefferson | 5 |
| Johnson | 20 |
| Jones | 0 |
| Keokuk | 0 |
| Kossuth | 0 |
| Lee | 0 |
| Linn | 24 |
| Louisa | 0 |
| Lucas | 0 |
| Lyon | 1 |
| Madison | 0 |
| Mahaska | 0 |
| Marion | 0 |
| Marshall | 1 |
| Mills | 0 |
| Mitchell | 0 |
| Monona | 1 |
| Monroe | 0 |
| Montgomery | 0 |
| Muscatine | 2 |
| O'Brien | 0 |
| Osceola | 0 |
| Page | 0 |
| Palo Alto | 1 |
| Plymouth | 1 |
| Pocahontas | 0 |
| Polk | 39 |
| Pottawattamie | 2 |
| Poweshiek | 5 |
| Ringgold | 1 |
| Sac | 0 |
| Scott | 10 |
| Shelby | 0 |
| Sioux | 1 |
| Story | 12 |
| Tama | 0 |
| Taylor | 0 |
| Union | 0 |
| Van Buren | 0 |
| Wapello | 0 |
| Warren | 0 |
| Washington | 2 |
| Wayne | 0 |
| Webster | 0 |
| Winnebago | 0 |
| Winneshiek | 1 |
| Woodbury | 4 |
| Worth | 0 |
| Wright | 0 |