# Iowa's 18th Senate district

The 18th District of the Iowa Senate is located in central Iowa, and is currently composed of part of Polk County.

## Current elected officials

Janet Petersen is the senator currently representing the 18th District.
The area of the 18th District contains two Iowa House of Representatives districts:
* The 35th District (represented by Sean Bagniewski)
* The 36th District (represented by Austin Baeth)
The district is also located in Iowa's 3rd congressional district, which is represented by Zach Nunn.

## List of representatives

| Representative | Party | Dates | Residence | Notes |
| William E. Leffingwell | Democrat | 1852-1853 | DeWitt, Iowa | |
| Julius J. Matthews | Whig | 1854-1855 | Lyons, Iowa | |
| Marquis Lafayette McPherson | Republican | 1856-1859 | Winterset, Iowa | |
| Jairus Edward Neal | Democrat | 1860-1863 | Knoxville, Iowa | |
| John Abbott Lake Crookham | Republican | 1864-1867 | Oskaloosa, Iowa | |
| John R. Needham | Republican | 1868 | Oskaloosa, Iowa | Senator Needham died in office in 1868. |
| John Nicholas Dixon | Republican | 1870-1871 | Mahaska County, Iowa | |
| James Addison Young | Republican | 1872-1875 | Oskaloosa, Iowa | Senator Young died in office in 1875. |
| Thomas Ritchie Gilmore | Republican | 1876-1877 | Mahaska County, Iowa | |
| Lafayette Young | Republican | 1878-1881 | Albia, Iowa | |
| Cephas B. Hunt | Republican | 1882-1885 | Greenfield, Iowa | |
| Lafayette Young | Republican | 1886-1889 | Albia, Iowa | |
| William Fiske Cleveland | Democrat | 1890-1893 | Harlan, Iowa | |
| Julian Phelps | Republican | 1894-1897 | Atlantic, Iowa | |
| Joseph Martin Emmert | Democrat | 1898-1901 | Atlantic, Iowa | |
| James E. Bruce | Republican | 1902-1910 | Atlantic, Iowa | |
| Thomas Henry Smith | Republican | 1911-1914 | Harlan, Iowa | |
| John Cramer Voorhees | Democrat | 1915-1918 | Anita, Iowa | Senator Voorhees died in office in 1918. |
| Julius A. Nelson | Republican | 1919-1926 | Cass County, Iowa | |
| Charles D. Booth | Republican | 1927-1934 | Harlan, Iowa | |
| Charles E. Malone | Democrat | 1935-1936 | Atlantic, Iowa | Senator Malone resigned in 1936 to become the postmaster of Atlantic. |
| Frank Pelzer | Republican | 1937-1944 | Marne, Iowa | Senator Pelzer died in office in 1944. |
| Edward Speer White | Republican | 1945-1946 | Harlan, Iowa | |
| Jay C. Colburn | Republican | 1947-1954 | Harlan, Iowa | |
| John David Shoeman | Republican | 1955-1962 | Atlantic, Iowa | |
| David O. Shaff | Republican | 1963-1966 | Clinton, Iowa | |
| Kenneth Benda | Republican | 1967-1968? | Hartwick, Iowa | |
| Joann Yesler Orr | Democrat | 1968-1970 | Grinnell, Iowa | Senator Orr filled a vacancy in 1968. The vacancy is for an unknown reason. |
| John L. Mowry | Republican | 1971-1972 | Marshalltown, Iowa | |
| Willard R. Hansen | Republican | 1973-1980 | Cedar Falls, Iowa | |
| Ted J. Anderson | Democrat | 1981-1982 | Waterloo, Iowa | |
| Robert M. Carr | Democrat | 1983-1989 | Dubuque, Iowa | Senator Carr resigned in 1989 to accept a position as Dubuque County Treasurer. |
| Michael W. Connolly | Democrat | 1990-2002 | Dubuque, Iowa | Senator Connolly was elected to district 18 during a special election in 1989. |
| Mary A. Lunby | Republican | 2003-2008 | Linn County, Iowa | |
| Swati A. Dandekar | Democrat | 2009-2011 | Marion, Iowa | Senator Dandekar resigned in 2011 to accept a position on the Iowa Utilities Board. |
| Liz Mathis | Democrat | 2011-2012 | DeWitt, Iowa | |
| Janet Petersen | Democrat | 2013-present | Des Moines, Iowa | |

## Historical district boundaries

Source:
| Description | Years effective | Notes |
| Cedar County Clinton County | 1852-1855 | From 1846 to 1857, district numbering was not utilized by the Iowa State Legislature. This convention was added with the passing of the 1857 Iowa Constitution. Numbering of districts pre-1857 is done as a matter of historic convenience. |
| Adair County Cass County Madison County Warren County | 1856-1859 | |
| Marion County | 1860-1863 | |
| Mahaska County | 1864-1877 | |
| Adair County Cass County Madison County | 1878-1883 | |
| Adair County Adams County Cass County | 1884-1887 | |
| Cass County Shelby County | 1888-1962 | |
| Clinton County | 1963-1966 | |
| Iowa County Poweshiek County | 1967-1970 | |
| Grundy County Marshall County | 1971-1972 | In 1970, the Iowa Legislature passed an amendment to the Iowa Constitution setting forth the rules for legislative redistricting in order to abide by the rules established by the Reynolds v. Sims Supreme Court case. The first reapportionment map created by the Republican controlled legislature was deemed unconstitutional, but was still used for the 1970 election. |
| Black Hawk County (partial) Primarily composed of Cedar Falls | 1973-1982 | |
| Dubuque County (partial) Primarily composed of Dubuque | 1983-2002 | Some minor boundary changes may have occurred after the redistricting of 1992. |
| Linn County (partial) Excluding Bertram Township College Township Marion Township (partial) Marion Township south of Marion and west of US-151 was not part of Senate District 18; the remainder was. Putnam Township Bertram Cedar Rapids Ely | 2003-2012 | |
| Polk County (partial) Webster Township (partial) Small section between I-35/I-80, the Des Moines River and Des Moines Des Moines (partial) Northwestern portions of the City | 2013-2022 | |
| Polk County (partial) Des Moines (partial) Western portions of the city | 2023-present |