5 things we're watching ahead of Iowa's June 2 primary election

Iowa voters are set to head to the polls on June 2 to settle intra-party primary battles up and down the ballot and choose nominees ahead of a consequential general election in November.

Polls are open from 7 a.m. to 8 p.m.

Republicans have enjoyed near-total control of the state for years. But the party faces national headwinds in 2026 as voters wrestle with Republican President Donald Trump's leadership in the White House and Republicans' control of Congress.

In Iowa, the political landscape has shifted significantly with the coming retirements of incumbent Gov. Kim Reynolds and U.S. Sen. Joni Ernst, both Republicans.

Democrats hope to take advantage, but face a steep disadvantage in getting voters registered for November.

Here's a look at what to watch on Primary Day as Democrats and Republicans look to set themselves up for success.

Will the Republican governor nomination remain unresolved until convention?

The GOP gubernatorial contest will be among the state's most-watched primary races as U.S. Rep. Randy Feenstra tries to put to bed challenges from four other Republican candidates.

The five Republicans on this year's primary ballot: state Rep. Eddie Andrews, Feenstra, businessman Zach Lahn, former state Rep. Brad Sherman and former state administrator Adam Steen. The winner will take on Democratic Auditor Rob Sand, who is unopposed in the primary.

Feenstra entered the race as the perceived frontrunner, backed by some of the state's top elected officials and with millions of dollars in fundraising at his disposal.

Trump waded into the contest on Friday, May 29, offering Feenstra his "complete and total endorsement."

But Feenstra has faced steep criticism, particularly from the state's MAGA base, for failing to show up to debates and many multi-candidate events.

Some campaigns have been openly organizing for the possibility that he does not clear the 35% threshold to earn the nomination outright on Election Day. If no candidate hits that mark, the nomination would be decided by grassroots delegates at a Republican state convention on June 13.

There are indications that Lahn is gaining momentum in the race.

He edged out Feenstra in fundraising from Jan. 1 to May 14, although Feenstra has raised more overall. And the Feenstra campaign has trained its attacks on Lahn with negative TV ads, suggesting they feel the need to block any momentum.

As results come in, Feenstra will need to perform well in his own 4th Congressional District, where there's an outsized concentration of Republican primary voters. If other candidates eat into his lead there, it could spell trouble for him overall.

Who will emerge from the U.S. Senate Democratic primary race?

The Democratic primary for U.S. Senate has seen state Rep. Josh Turek and state Sen. Zach Wahls battling for weeks in a closely watched contest.

Each has made the case that he is the most electable in a general election matchup against Republican frontrunner U.S. Rep. Ashley Hinson. But Turek is viewed as the more moderate figure compared with Wahls' more progressive resume.

Early polling showed the pair running about even in the primary race. But Turek has taken a sizeable lead in more recent surveys after a deluge of outside money has come in to support his candidacy.

VoteVets, a Democratic-aligned PAC, has spent $10 million on television and digital advertising and direct mail to support Turek since March 23, according to reports with the Federal Election Commission.

How will GOP challengers perform against establishment candidates?

In 2024, MAGA-aligned outsider candidates challenged Iowa's more establishment Republican politicians and have earned substantial slices of the electorate despite lower name ID and smaller bank accounts, although they fell short of toppling incumbents.

At the time, it appeared to signal a rightward shift of Iowa's GOP base.

A similar dynamic could play out across a range of primaries this year as outsider, grassroots candidates challenge establishment Republicans.

In Iowa's 1st Congressional District, incumbent U.S. Rep. Mariannette Miller-Meeks is facing a repeat challenge from David Pautsch, a businessman and founder of the Quad Cities Prayer Breakfast. Pautsch challenged Miller-Meeks in 2024 and, although he lost, he took 44% of the vote.

In the open U.S. Senate race, former state Sen. Jim Carlin has tried to lay claim to the MAGA mantle even as Trump has endorsed Hinson.

And in the auditor's race, grassroots favorite Abigail Maas, an Iowa County supervisor, is going up against Lt. Gov. Chris Cournoyer, whom Reynolds backs.

Will 2024's rightward shift continue this year? And if those outsider candidates gain a substantial share of the primary vote, what might that say about Iowa Republican voters ahead of a competitive general election year?

Will incumbents prevail in Republican legislative primaries?

Republicans have controlled the Iowa House and Senate for the past decade, but several sitting lawmakers face primary challenges this year that could change the makeup of the party's majorities.

There are eight competitive Republican primaries for Iowa Senate seats on the ballot, including four involving sitting Republican senators.

Fifteen Iowa House seats have competitive Republican primaries. And 10 of those feature challenges to a sitting GOP state representative.

Several of those races are playing out in central Iowa, including in Senate District 23, where state Sen. Mike Bousselot, R-Ankeny, is running against Wes Enos of Bondurant.

State Rep. Brian Lohse, R-Bondurant, faces a challenge from Austin Stubbs in House District 45.

And Rep. Carter Nordman, R-Dallas Center, is competing with Jeremy King in House District 47.

Independent groups are getting involved, with Americans for Prosperity spending to support Bousselot and Nordman and to oppose Lohse.

The Family Leader is spending money to support Stubbs and oppose Lohse.

In House District 51, the American Policy Project is spending money opposing Shane Heintz, who is challenging Rep. Brett Barker, R-Nevada.

What does voter turnout and party registration look like ahead of primary day?

Voter turnout could provide some insight into which party is more eager to vote this year.

Democrats overperformed in a series of special elections in 2025, thanks in part to high party voter turnout. But Republicans still hold a nearly 200,000-voter registration advantage over Democrats as of May.

A week out from the election, Iowa Secretary of State Paul Pate said turnout for early voting, which began May 13, is behind last year's. He noted primary turnout is driven largely by party mobilization and excitement over individual candidates and races on the ballot.

"We have a lot of people running for governor, and we've got some people voting for U.S. Senate, and we have congressional primaries in various parts of the state," Pate told reporters during a May 26 news conference on election security. "I suspect that there'll be more activity here this week."

Brianne Pfannenstiel is the chief politics reporter for the Des Moines Register. She writes about campaigns, elections and the Iowa Caucuses. Reach her at [email protected] or 515-284-8244. Follow her on X at @brianneDMR.

Stephen Gruber-Miller is the Capitol bureau chief for the Des Moines Register. He can be reached by email at [email protected], by phone at 515-284-8169 or on X at @sgrubermiller.

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