Fifth in a series interpreting the results of Iowa’s 2024 state and federal elections.

Matthew P. Thornburg is an associate professor at Misericordia University who studies elections. His mother’s side of the family hails from Greene and O’Brien counties, and he maintains close ties to Iowa and its politics.

In precincts lying in the path of the Summit Pipeline, Randy Feenstra underperformed the rest of his district slightly. However, most voters there and elsewhere in the fourth Congressional district remained straight ticket Republicans. Much of Feenstra’s mild underperformance arose from voters in O’Brien County, home county of his Republican primary opponent Kevin Virgil.

Carbon dioxide pipelines remain the issue Iowa Republicans wish would go away. While most political issues in the state are subsumed into the greater red vs. blue polarization of the country—where Republicans in Iowa enjoy the advantage–CO₂  pipelines create an intraparty split between the Iowa GOP establishment and some in the party’s conservative wing.

Ground zero for that tension is Iowa’s fourth Congressional district, where CO₂ pipelines were a prominent issue in both the Republican primary and general election.

Kevin Virgil challenged incumbent U.S. Representative Randy Feenstra for the Republican nomination in the district and captured almost 40 percent of the vote. Resistance to CO₂ pipelines and the use of eminent domain to build them served as a centerpiece to Virgil’s campaign. The cross-party nature of the conflict was evident when Virgil rankled the Iowa Republican establishment by endorsing Feenstra’s Democratic challenger, Ryan Melton—though he later walked that back somewhat and encouraged his supporters to write in his own name for the general election.

Melton also made CO₂ pipelines a central issue of his campaign—as did Libertarian Charles Aldrich, who was struck from the ballot and also encouraged his supporters to write in his name.

Both the intraparty nature of the issue and its centrality to this year’s IA-04 election created a perfect storm for a local concern to potentially disrupt the strong Republican partisanship of the western Iowa Congressional district. I test here whether voters in precincts crossed by the Summit CO₂ pipeline (which the Iowa Utilities Commission recently approved) behaved differently from those residing in other precincts in their vote for U.S. representative in the fourth district.

COMPARING “PIPELINE PRECINTS” TO OTHERS

The proposed Summit Carbon Solutions pipeline crosses nineteen of the district’s 36 counties. Those precincts crossed by the Summit footprint, which I will call “pipeline precincts,” represent 14.5 percent of all precincts in IA-04. By their nature they are more Republican than much of the district, being rural and the majority located in the deep red Sioux Falls and Sioux City media markets, which remain the core of Feenstra’s support.

Since those differences likely confound a straightforward comparison of Feenstra’s support in pipeline precincts versus non-pipeline precincts, I first examine whether Feenstra outperformed the Republican baseline of support for Donald Trump in each precinct.

Over the 462 precincts located in the fourth Congressional district, Feenstra ran 1.84 points ahead of Trump on average. (This weights all districts equally rather than by number of voters, so the actual difference in vote share district-wide is different.)

However, in pipeline precincts, Feenstra’s advantage over Trump was just 1.15 points, compared to non-pipeline precincts where the advantage was 1.96 points. The difference is small, but there is only a very small chance it was produced by random statistical noise. Put another way, in a little under a quarter of pipeline precincts (23.9 percent), Feenstra actually received a smaller vote share than Trump compared to just 13.4 percent of non-pipeline precincts.

Did this small difference between pipeline and non-pipeline precincts translate into a greater vote share than expected for Democrat Ryan Melton in the former? The answer is yes, but not by much. Melton underperformed Kamala Harris in IA-04 precincts on average by 0.54 points. Once again, there was a difference between pipeline and non-pipeline precincts: Melton ran 0.20 points behind Harris on average, but did a little over half a point worse in non-pipeline precincts (0.60 points behind on average).

The difference between Melton’s performance in pipeline versus non-pipeline precincts is smaller than the difference between Feenstra’s performance in the two types of precincts.

Since Virgil and Aldrich encouraged voters to write in their names as an alternative to both Feenstra and Melton, I examine whether there were more write-in votes recorded in pipeline precincts than non-pipeline precincts. About 0.32 percent of votes for Congress in the fourth district were write-ins, on average across precincts. In non-pipeline precincts, an average of 0.29 percent of ballots cast were write-ins, but in pipeline precincts that average was 0.49 percent of votes.

THE O’BRIEN COUNTY ANOMALY

Much of the difference between pipeline and non-pipeline precincts comes from a single county: O’Brien. Virgil lives in that county, which witnessed the largest single drop in Feenstra’s GOP primary support in a county from 2020 to 2024 (68.6 percent to 39.4 percent).

Separating pipeline and non-pipeline precincts by whether they are in O’Brien County shows that in pipeline precincts in O’Brien County, Feenstra underperformed Trump by almost three points. Given that Feenstra outperformed Trump in precincts on average by 1.84 points in the district overall, that is a significant underperformance.

This is partially due to Melton outperforming Harris by about 1.25 points in these precincts, an overperformance matched nowhere else consistently in IA-04.

O’Brien pipeline precincts also averaged more than 3 percent of the House vote as write-ins. Among the 462 precincts, three of the six with the highest write-in percentages were pipeline precincts in O’Brien County.

While county auditors do not release write-in vote totals to the public unless a candidate receives more than 5 percent of the vote for a given office, it is likely most write-in votes in O’Brien pipeline precincts were for Virgil.

Overall, while these differences between pipeline and non-pipeline precincts are real, their magnitude is notably small and easy to miss amid the overall general election results. Feenstra ran ahead of Trump in the 2024 election; no small feat. And for the contentiousness of the pipeline issue in the fourth district this year, Feenstra appeared to lose only about 0.8 points of support in the precincts where a pipeline will go.

However, the likely salience of the pipeline issue in O’Brien County, combined with Virgil’s primary challenge gaining traction there, affected the results more than anywhere else in the district.

---

Top image: Attendees at a “No Eminent Domain! No Carbon Pipelines!” rally at the Iowa State Capitol on January 10, 2024. Photo by Gage Skidmore from Surprise, AZ, United States of America, CC BY-SA 2.0 https://creativecommons.org/licenses/by-sa/2.0, via Wikimedia Commons