Adams |
| Candidate | Party | Votes |
|---|
| Robert S. O'Brien | D | 2520 |
| William B. (Bill) Pilkey | R | 1793 |
| Mack J.T. Barnette | L | 188 |
Asotin |
| Candidate | Party | Votes |
|---|
| Robert S. O'Brien | D | 3887 |
| William B. (Bill) Pilkey | R | 2430 |
| Mack J.T. Barnette | L | 311 |
Benton |
| Candidate | Party | Votes |
|---|
| Robert S. O'Brien | D | 22758 |
| William B. (Bill) Pilkey | R | 18942 |
| Mack J.T. Barnette | L | 2078 |
Chelan |
| Candidate | Party | Votes |
|---|
| Robert S. O'Brien | D | 10223 |
| William B. (Bill) Pilkey | R | 7503 |
| Mack J.T. Barnette | L | 480 |
Clallam |
| Candidate | Party | Votes |
|---|
| Robert S. O'Brien | D | 12626 |
| William B. (Bill) Pilkey | R | 8587 |
| Mack J.T. Barnette | L | 975 |
Clark |
| Candidate | Party | Votes |
|---|
| Robert S. O'Brien | D | 40952 |
| William B. (Bill) Pilkey | R | 26960 |
| Mack J.T. Barnette | L | 4679 |
Columbia |
| Candidate | Party | Votes |
|---|
| Robert S. O'Brien | D | 1036 |
| William B. (Bill) Pilkey | R | 792 |
| Mack J.T. Barnette | L | 51 |
Cowlitz |
| Candidate | Party | Votes |
|---|
| Robert S. O'Brien | D | 17268 |
| William B. (Bill) Pilkey | R | 8799 |
| Mack J.T. Barnette | L | 786 |
Douglas |
| Candidate | Party | Votes |
|---|
| Robert S. O'Brien | D | 5108 |
| William B. (Bill) Pilkey | R | 3646 |
| Mack J.T. Barnette | L | 304 |
Ferry |
| Candidate | Party | Votes |
|---|
| Robert S. O'Brien | D | 1189 |
| William B. (Bill) Pilkey | R | 651 |
| Mack J.T. Barnette | L | 45 |
Franklin |
| Candidate | Party | Votes |
|---|
| Robert S. O'Brien | D | 6238 |
| William B. (Bill) Pilkey | R | 4201 |
| Mack J.T. Barnette | L | 286 |
Garfield |
| Candidate | Party | Votes |
|---|
| Robert S. O'Brien | D | 733 |
| William B. (Bill) Pilkey | R | 517 |
| Mack J.T. Barnette | L | 33 |
Grant |
| Candidate | Party | Votes |
|---|
| Robert S. O'Brien | D | 9639 |
| William B. (Bill) Pilkey | R | 6928 |
| Mack J.T. Barnette | L | 554 |
Grays Harbor |
| Candidate | Party | Votes |
|---|
| Robert S. O'Brien | D | 17419 |
| William B. (Bill) Pilkey | R | 5952 |
| Mack J.T. Barnette | L | 1055 |
Island |
| Candidate | Party | Votes |
|---|
| Robert S. O'Brien | D | 9840 |
| William B. (Bill) Pilkey | R | 8569 |
| Mack J.T. Barnette | L | 783 |
Jefferson |
| Candidate | Party | Votes |
|---|
| Robert S. O'Brien | D | 5093 |
| William B. (Bill) Pilkey | R | 2907 |
| Mack J.T. Barnette | L | 325 |
King |
| Candidate | Party | Votes |
|---|
| Robert S. O'Brien | D | 358475 |
| William B. (Bill) Pilkey | R | 202229 |
| Mack J.T. Barnette | L | 21269 |
Kitsap |
| Candidate | Party | Votes |
|---|
| Robert S. O'Brien | D | 37232 |
| William B. (Bill) Pilkey | R | 23606 |
| Mack J.T. Barnette | L | 2344 |
Kittitas |
| Candidate | Party | Votes |
|---|
| Robert S. O'Brien | D | 6465 |
| William B. (Bill) Pilkey | R | 3677 |
| Mack J.T. Barnette | L | 358 |
Klickitat |
| Candidate | Party | Votes |
|---|
| Robert S. O'Brien | D | 3505 |
| William B. (Bill) Pilkey | R | 2363 |
| Mack J.T. Barnette | L | 297 |
Lewis |
| Candidate | Party | Votes |
|---|
| Robert S. O'Brien | D | 13217 |
| William B. (Bill) Pilkey | R | 8022 |
| Mack J.T. Barnette | L | 992 |
Lincoln |
| Candidate | Party | Votes |
|---|
| Robert S. O'Brien | D | 2672 |
| William B. (Bill) Pilkey | R | 2003 |
| Mack J.T. Barnette | L | 188 |
Mason |
| Candidate | Party | Votes |
|---|
| Robert S. O'Brien | D | 9667 |
| William B. (Bill) Pilkey | R | 4670 |
| Mack J.T. Barnette | L | 582 |
Okanogan |
| Candidate | Party | Votes |
|---|
| Robert S. O'Brien | D | 6873 |
| William B. (Bill) Pilkey | R | 4572 |
| Mack J.T. Barnette | L | 679 |
Pacific |
| Candidate | Party | Votes |
|---|
| Robert S. O'Brien | D | 5383 |
| William B. (Bill) Pilkey | R | 1834 |
| Mack J.T. Barnette | L | 475 |
Pend Oreille |
| Candidate | Party | Votes |
|---|
| Robert S. O'Brien | D | 2191 |
| William B. (Bill) Pilkey | R | 1443 |
| Mack J.T. Barnette | L | 139 |
Pierce |
| Candidate | Party | Votes |
|---|
| Robert S. O'Brien | D | 106337 |
| William B. (Bill) Pilkey | R | 60229 |
| Mack J.T. Barnette | L | 4423 |
San Juan |
| Candidate | Party | Votes |
|---|
| Robert S. O'Brien | D | 2537 |
| William B. (Bill) Pilkey | R | 2050 |
| Mack J.T. Barnette | L | 303 |
Skagit |
| Candidate | Party | Votes |
|---|
| Robert S. O'Brien | D | 18498 |
| William B. (Bill) Pilkey | R | 11310 |
| Mack J.T. Barnette | L | 1181 |
Skamania |
| Candidate | Party | Votes |
|---|
| Robert S. O'Brien | D | 1795 |
| William B. (Bill) Pilkey | R | 1036 |
| Mack J.T. Barnette | L | 169 |
Snohomish |
| Candidate | Party | Votes |
|---|
| Robert S. O'Brien | D | 86661 |
| William B. (Bill) Pilkey | R | 55053 |
| Mack J.T. Barnette | L | 6174 |
Spokane |
| Candidate | Party | Votes |
|---|
| Robert S. O'Brien | D | 82416 |
| William B. (Bill) Pilkey | R | 55278 |
| Mack J.T. Barnette | L | 5393 |
Stevens |
| Candidate | Party | Votes |
|---|
| Robert S. O'Brien | D | 6121 |
| William B. (Bill) Pilkey | R | 5052 |
| Mack J.T. Barnette | L | 689 |
Thurston |
| Candidate | Party | Votes |
|---|
| Robert S. O'Brien | D | 37821 |
| William B. (Bill) Pilkey | R | 18535 |
| Mack J.T. Barnette | L | 2915 |
Wahkiakum |
| Candidate | Party | Votes |
|---|
| Robert S. O'Brien | D | 1012 |
| William B. (Bill) Pilkey | R | 440 |
| Mack J.T. Barnette | L | 18 |
Walla Walla |
| Candidate | Party | Votes |
|---|
| Robert S. O'Brien | D | 9823 |
| William B. (Bill) Pilkey | R | 7137 |
| Mack J.T. Barnette | L | 835 |
Whatcom |
| Candidate | Party | Votes |
|---|
| Robert S. O'Brien | D | 26235 |
| William B. (Bill) Pilkey | R | 16980 |
| Mack J.T. Barnette | L | 2300 |
Whitman |
| Candidate | Party | Votes |
|---|
| Robert S. O'Brien | D | 7713 |
| William B. (Bill) Pilkey | R | 6355 |
| Mack J.T. Barnette | L | 885 |
Yakima |
| Candidate | Party | Votes |
|---|
| Robert S. O'Brien | D | 31305 |
| William B. (Bill) Pilkey | R | 24862 |
| Mack J.T. Barnette | L | 1367 |