| REP | NAT | DEM | |
|---|---|---|---|
| Counties | Mike Crapo | George J. Mansfeld | Bill Mauk |
| Ada | 60,833 | 1,700 | 29,543 |
| Adams | 1,217 | 47 | 382 |
| Bannock | 14,055 | 438 | 8,714 |
| Bear Lake | 1,563 | 61 | 422 |
| Benewah | 1,980 | 78 | 778 |
| Bingham | 8,741 | 192 | 2,674 |
| Blaine | 2,667 | 126 | 2,645 |
| Boise | 1,561 | 80 | 635 |
| Bonner | 7,038 | 374 | 3,557 |
| Bonneville | 20,011 | 372 | 5,025 |
| Boundary | 2,063 | 109 | 804 |
| Butte | 808 | 30 | 344 |
| Camas | 325 | 19 | 102 |
| Canyon | 23,531 | 662 | 8,403 |
| Caribou | 1,924 | 52 | 361 |
| Cassia | 4,798 | 111 | 911 |
| Clark | 312 | 9 | 70 |
| Clearwater | 1,898 | 70 | 1,069 |
| Custer | 1,200 | 38 | 393 |
| Elmore | 3,746 | 107 | 1,262 |
| Franklin | 2,805 | 67 | 383 |
| Fremont | 3,315 | 75 | 566 |
| Gem | 3,438 | 121 | 1,280 |
| Gooding | 2,953 | 92 | 969 |
| Idaho | 4,223 | 135 | 1,249 |
| Jefferson | 5,039 | 100 | 893 |
| Jerome | 3,673 | 96 | 940 |
| Kootenai | 20,000 | 713 | 8,649 |
| Latah | 6,538 | 283 | 5,076 |
| Lemhi | 2,668 | 85 | 634 |
| Lewis | 901 | 35 | 397 |
| Lincoln | 859 | 29 | 325 |
| Madison | 5,855 | 64 | 549 |
| Minidoka | 4,146 | 118 | 1,088 |
| Nez Perce | 7,630 | 261 | 4,996 |
| Oneida | 965 | 26 | 243 |
| Owyhee | 2,004 | 39 | 560 |
| Payette | 3,822 | 104 | 1,321 |
| Power | 1,484 | 27 | 670 |
| Shoshone | 2,080 | 128 | 1,745 |
| Teton | 1,242 | 45 | 493 |
| Twin Falls | 12,461 | 381 | 4,411 |
| Valley | 2,158 | 66 | 988 |
| Washington | 2,436 | 68 | 856 |
| TOTAL | 262,966 | 7,833 | 107,375 |
| Plurality | 155,591 | ||
| Percentage | 69.5% | 2.1% | 28.4% |