UPDATE: Unofficial results show Brown won this primary by 2,546 votes to 2,273 (52.8 percent to 47.1 percent). Original post follows.

Two Iowa state senators and six state representatives face competition for their party’s nomination in the June 4 primary. The most intriguing match-up is unfolding in Senate district 30.

Two-term Republican State Senator Waylon Brown has a huge financial advantage and the backing of powerful interest groups. His opponent Doug Campbell, a retired pharmacist and former Mason City school board member, is running a low-budget campaign powered by grassroots outrage over a proposed CO2 pipeline.

The outcome should signal whether the controversy over property rights in rural Iowa is salient enough in GOP circles to overcome the advantages of incumbency. If Campbell prevails, Senate Republicans may feel pressure to consider eminent domain legislation in 2025, after blocking all such bills in the Commerce Committee for the last several years.

Editor’s note: This analysis has been updated with unofficial results from all the races. Original post follows.

The major parties have spent hundreds of thousands of dollars on the most competitive 2022 Iowa House and Senate races.

This post highlights seven state Senate districts where one or both parties have spent large sums, and another seven where even without a big investment by Democrats or Republicans, the results could shed light on political trends.

All voter registration totals listed below come from the Iowa Secretary of State’s office, as reported on November 1. All absentee ballot figures come from the Secretary of State’s office, as reported on November 7. All past election results come from the map Josh Hughes created in Dave’s Redistricting App.

All figures for in-kind spending by the Iowa Democratic Party or Republican Party of Iowa come from filings with the Iowa Ethics and Campaign Disclosure Board. I focus on in-kind spending, because candidates in battleground Iowa legislative races typically give most of their funds to the state party. The party then covers the bulk of the large expenditures for direct mail and/or television, radio, and digital advertising.