District 18 of the Oregon State Senate comprises parts of central Washington County centered around Aloha and encompassing parts of Beaverton and Hillsboro. It is composed of Oregon House districts 35 and 36. It is currently represented by Democrat Wlnsvey Campos of Aloha.
District boundaries have changed over time. Therefore, senators before 2021 may not represent the same constituency as today. From 1993 until 2003, the district covered parts of the western Willamette Valley; from 2003 until 2013, it covered Tigard and parts of southwest and downtown Portland; and from 2013 until 2023, it only shifted slightly, covering more of downtown Portland as well as the city of Durham and a small chunk of Clackamas County. The results are as follows [1] :
| Year | Candidate | Party | Percent | Opponent | Party | Percent | Opponent | Party | Percent |
|---|---|---|---|---|---|---|---|---|---|
| 1982 | Clifford W. Trow | Democratic | 62.4% | Bob Jackson | Republican | 37.6% | No third candidate | ||
| 1986 | Clifford W. Trow | Democratic | 58.4% | Win Eaton | Republican | 41.6% | |||
| 1990 | Clifford W. Trow | Democratic | 51.7% | Kathleen Kessinger | Republican | 48.3% | |||
| 1994 | Clifford W. Trow | Democratic | 54.9% | Rich Rodeman | Republican | 45.1% | |||
| 1998 | Clifford W. Trow | Democratic | 58.2% | Win Eaton | Republican | 41.8% | |||
| 2004 | Ginny Burdick | Democratic | 62.5% | John Wight | Republican | 34.1% | |||
| 2008 | Ginny Burdick | Democratic | 70.0% | John Wight | Republican | 29.7% | |||
| 2012 | Ginny Burdick | Democratic | 69.3% | Suzanne Gallagher | Republican | 30.4% | |||
| 2016 | Ginny Burdick | Democratic | 97.4% | Unopposed | |||||
| 2020 | Ginny Burdick | Democratic | 95.8% | ||||||
| 2022 [lower-alpha 1] | Wlnsvey Campos | Democratic | 56.5% | Kimberly Rice | Republican | 33.0% | Rich Vial | [lower-alpha 2] | 10.4% |
District 4 of the Oregon State Senate comprises central Lane County centered around Eugene and Springfield. It is composed of Oregon House districts 7 and 8. It is currently represented by Democrat Floyd Prozanski of Eugene.
District 7 of the Oregon State Senate comprises parts of northern Lane County in the Eugene metropolitan area. It is composed of Oregon House districts 13 and 14. It is currently represented by Democrat James Manning Jr. of Eugene.
District 8 of the Oregon State Senate comprises northwestern Linn County, northeastern Benton County, and southern Marion County centered around Albany and Corvallis. It is composed of Oregon House districts 15 and 16. It is currently represented by Democrat Sara Gelser Blouin of Corvallis.
District 9 of the Oregon State Senate comprises the rural areas in eastern Marion and Linn counties as well as southern Clackamas County. It is composed of Oregon House districts 17 and 18. It is currently represented by Republican Fred Girod of Stayton.
District 10 of the Oregon State Senate comprises parts of Marion and Polk counties, including much of south and west Salem as well as Independence and Monmouth. The district is composed of Oregon House districts 19 and 20.
District 11 of the Oregon State Senate comprises parts of Marion County, including Keizer, Woodburn and much of Salem. It contains Oregon House districts 21 and 22. It is currently represented by Republican Kim Thatcher of Keizer.
Oregon's 14th Senate district comprises parts of Washington and Multnomah counties, including much of Beaverton and southwest Portland. It contains Oregon House districts 27 and 28. It is currently represented by Democrat Kate Lieber of Beaverton.
District 15 of the Oregon State Senate comprises central Washington County, including most of Hillsboro as well as Forest Grove and Cornelius. It is composed of Oregon House districts 29 and 30. It is currently represented by Democrat Janeen Sollman of Hillsboro.
District 16 of the Oregon State Senate comprises all of Clatsop, Columbia, and Tillamook counties as well as western portions of Multnomah and Washington counties and a small sliver of northern Yamhill County. It consists of Oregon House districts 31 and 32. It is currently represented by Republican Suzanne Weber.
District 17 of the Oregon State Senate comprises parts of Multnomah and Washington counties encompassing much of northwest Portland and suburbs of Beaverton. It is composed of Oregon House districts 33 and 34. It is currently represented by Democrat Elizabeth Steiner of Portland.
District 19 of the Oregon State Senate comprises northwestern Clackamas, southwestern Multnomah, and southeastern Washington counties and includes Lake Oswego, Tualatin, and West Linn as well as Portland's South Waterfront. It is composed of Oregon House districts 37 and 38. It is currently represented by Democrat Rob Wagner of Lake Oswego.
Oregon's 21st Senate district comprises parts of Clackamas and Multnomah counties, including Milwaukie and Oak Grove as well as parts of southeast Portland. It is composed of Oregon House districts 41 and 42. The district is currently represented by Democrat Kathleen Taylor of Portland.
District 22 of the Oregon State Senate comprises parts of north and northeast Portland. The district is composed of Oregon House districts 43 and 44. It is currently represented by Democrat Lew Frederick of Portland.
District 23 of the Oregon State Senate comprises parts of Portland and the entirety of Maywood Park in Multnomah County. The district is composed of Oregon House districts 45 and 46. It is currently represented by Democrat Michael Dembrow of Portland.
District 24 of the Oregon State Senate comprises parts of Clackamas and Multnomah counties. Since January 2021, it has been represented by Democrat Kayse Jama, who was appointed unanimously by the Clackamas and Multnomah County Boards of Commissioners to replace Shemia Fagan after she was elected Oregon Secretary of State.
District 26 of the Oregon State Senate comprises all of Hood River County, as well as parts of Clackamas, Multnomah, and Wasco counties. The district is composed of Oregon House districts 51 and 52. It is currently represented by Republican Daniel Bonham of Hood River.
District 27 of the Oregon State Senate comprises parts of Deschutes County centered around greater Bend. The district is composed of Oregon House districts 53 and 54. It is currently represented by Republican Tim Knopp of Bend.
District 28 of the Oregon State Senate comprises all of Klamath County as well as parts of Deschutes and Jackson counties. The district is composed of Oregon House districts 55 and 56. It is currently represented by Republican Dennis Linthicum of Bonanza.
District 29 of the Oregon State Senate comprises all of Gilliam, Morrow, Sherman, Umatilla, Union, Wallowa, and Wheeler counties, as well as parts of Clackamas, Jefferson, Marion, and Wasco counties. The district is composed of Oregon House districts 57 and 58. It is currently represented by Republican Bill Hansell of Athena.
District 30 of the Oregon State Senate comprises all of Baker, Crook, Grant, Harney, Lake, and Malheur counties, as well as parts of Deschutes and Jefferson counties. The district is composed of Oregon House districts 59 and 60 and is the largest state Senate district in Oregon. It is currently represented by Republican Lynn Findley of Vale.