Iowa State Senate District 8

Iowa State Senate District 8 is represented by Mark Costello (R).

As of the 2020 Census, Iowa state senators represented an average of 63,848 residents. After the 2010 Census, each member represented 61,076 residents.

About the chamber

Members of the Iowa State Senate serve four-year terms and are not subject to term limits. Half of the senate is up for re-election every two years. Iowa state senators assume office on the first day of January which is not a Sunday or legal holiday.^[1]^[2]

Qualifications

See also: State legislature candidate requirements by state

The Iowa Constitution states, "Senators shall be chosen for the term of four years, at the same time and place as representatives; they shall be twenty-five years of age, and possess the qualifications of representatives as to residence and citizenship."^[3]

Salaries

See also: Comparison of state legislative salaries

State legislative salaries, 2024^[4]
Salary	Per diem
$25,000/year	$178/day for legislators who live outside of Polk County. $133.50/day for legislators who live within Polk County.

Vacancies

See also: How vacancies are filled in state legislatures

If there is a vacancy in the Iowa General Assembly, the vacant seat must be filled by a special election. The governor of Iowa is required within five days of a vacancy in the General Assembly to call for a special election. If the vacancy happens in session or within 45 days of the session convening, the governor must call for an election as soon as possible with at least an 18-day notice. All other special elections require a 40-day notice as long the election does not happen on the same day as a school election within the district.^[5]

See sources: Iowa Code § 69.14

District map

Redistricting

2020-2022

See also: Redistricting in Iowa after the 2020 census

On November 4, 2021, Iowa Gov. Kim Reynolds (R) signed new congressional and state legislative maps into law after the state's Legislative Services Agency had proposed them on October 21, 2021. The Iowa legislature approved the maps on October 28, 2021, by a vote of 48-1 in the state Senate and 93-2 in the state House.^[6] The legislature could only vote to approve or reject the maps and could not make any amendments. These maps took effect for Iowa's 2022 congressional and legislative elections.

How does redistricting in Iowa work? The Legislative Services Agency prepares redistricting plans for approval by the Iowa State Legislature. According to All About Redistricting, the Legislative Services Agency (LSA) consists of "civil servants committed to nonpartisanship and otherwise charged with tasks like legal and fiscal analysis of state legislation and state government oversight." The LSA is assisted by a commission, which consists of the following members:^[7]

one member selected by the majority leader of the Iowa State Senate
one member selected by the majority leader of the Iowa House of Representatives
one member selected by the minority leader of the Iowa State Senate
one member selected by the minority leader of the Iowa House of Representatives
one member selected by the first four members

The members of this commission cannot "hold partisan public office or an office in a political party, and none may be a relative or employee of a federal or state legislator (or the legislature as a whole)."^[7]

Working with this commission, the LSA drafts congressional and state legislative district lines. The maps are presented as a single bill to the state legislature, which may approve or reject the bill without altering it (the legislature can provide feedback). If the legislature rejects the plan, the LSA must draft a second proposal. If the legislature rejects the second proposal, the LSA must draft a third, and final, set of maps. If the legislature rejects this plan, it may then approve its own maps. Since the implementation of this process in 1980, the state legislature has never chosen not to approve an LSA proposal. Redistricting plans are also subject to gubernatorial veto. In addition, the legislature may repeal or revise the maps at any time, though it has never done so.^[7]

State law establishes the following criteria for both congressional and state legislative districts:^[7]

Districts must be "convenient and contiguous."
Districts must "preserve the integrity of political subdivisions like counties and cities."
Districts must "to the extent consistent with other requirements, [be] reasonably compact–defined in terms of regular polygons, comparisons of length and width, and overall boundary perimeter."

In addition, state House districts are required to be contained within state Senate districts "where possible, and where not in conflict with the criteria above." It is explicit in state law that district lines cannot be drawn "to favor a political party, incumbent, or other person or group."^[7]

Iowa State Senate District 8
until January 2, 2023

Click a district to compare boundaries.

Iowa State Senate District 8
starting January 3, 2023

Click a district to compare boundaries.

Elections

2024

General election

General election for Iowa State Senate District 8

Incumbent Mark Costello defeated Ryan Lee Roenfeld in the general election for Iowa State Senate District 8 on November 5, 2024.

		Candidate	%	Votes
✔		Mark Costello (R)	70.5	25,069
	Submit photo	Ryan Lee Roenfeld (D)	29.3	10,432
		Other/Write-in votes	0.2	73

	Incumbents are bolded and underlined. The results have been certified. Source	Total votes: 35,574
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Democratic primary election

Democratic primary for Iowa State Senate District 8

Ryan Lee Roenfeld advanced from the Democratic primary for Iowa State Senate District 8 on June 4, 2024.

		Candidate	%	Votes
✔	Submit photo	Ryan Lee Roenfeld	99.1	573
		Other/Write-in votes	0.9	5

	There were no incumbents in this race. The results have been certified. Source	Total votes: 578
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Republican primary election

Republican primary for Iowa State Senate District 8

Incumbent Mark Costello advanced from the Republican primary for Iowa State Senate District 8 on June 4, 2024.

	Candidate	%	Votes
✔	Mark Costello	98.1	3,838
	Other/Write-in votes	1.9	73

	Incumbents are bolded and underlined. The results have been certified. Source	Total votes: 3,911
= candidate completed the Ballotpedia Candidate Connection survey.
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