Josh Turek, smiling and self-possessed, went in and out of his polling place in the gym of the Community of Christ church near his house in Council Bluffs.
“Campaigns are about momentum, and I feel like we’ve got a lot of momentum,” he said.
He affixed an “I voted” sticker to his shirt.
So began last day of the more than yearlong Senate primary in Iowa to determine which of the two Democrats on the ballot would get to run against Representative Ashley Hinson, the likely Republican nominee, in November. Party officials in Washington and the grass-roots faithful across Iowa, which is almost entirely controlled by Republicans, believe they have a chance to win a U.S. Senate seat for the first time since Tom Harkin was re-elected to a fifth term in 2008.
Mr. Turek, 47, is a state representative who lives in Council Bluffs on the more conservative western side of the state. He was born with spina bifida and won two gold medals in wheelchair basketball in the Paralympics before narrowly winning his spot in Iowa’s House and succeeding a Democrat in a Trump-supporting area in 2022. He has been buoyed by roughly $10 million of outside spending from Washington leaders and groups. He has been endorsed by Mr. Harkin; Pete Buttigieg, the former transportation secretary; and four sitting senators. His father, who voted twice for former President Barack Obama and three times for President Trump, had to change his registration from Republican to vote for his son.
Zach Wahls, 34, is a state senator who lives in Coralville, on the more liberal eastern side of the state. He came to political prominence at 19 in 2011, when he defended his lesbian mothers in a speech at the Iowa Capitol that was widely shared online. Even though he has more political experience than Mr. Turek, he has run a fervently anti-establishment campaign — pledging to not support Senator Chuck Schumer, the Democratic leader; pitching himself as the more credible outsider; and painting Mr. Turek as insider-aided, if not an insider on his own. He has been endorsed by Senator Elizabeth Warren, Democrat of Massachusetts; an array of unions and their bosses; and state lawmakers. If he were elected, he would be the youngest senator by a half decade.
Mr. Turek was scheduled to have his watch party on Tuesday at the Loft DSM, an industrial-chic event venue in Des Moines, while Mr. Wahls was set to have his at ReUnion Brewery in Iowa City. Polls close at 8 p.m. The latest surveys have had Mr. Turek in the lead.
“Any Democrat who wants to earn back trust in red and rural areas that we’ve lost — and that should be every Democrat — should be taking notes on Josh Turek,” said Representative Jake Auchincloss of Massachusetts. Mr. Auchincloss is the chairman of Majority Democrats, a group that is aligned with the Bench, an organization that supports the next generation of Democratic leaders and has endorsed Mr. Turek.
Mr. Wahls said he was optimistic about his own chances.
“As we head into the homestretch, I’m feeling great about the conversations we’re having at our events, on the phones and on the doors,” Mr. Wahls said on Tuesday afternoon. “Our message is resonating with the many Iowa voters who are still undecided, despite $10 million of outside spending. We’re carefully following the early vote numbers and feel good about how they look as we head into tonight’s results.”
Mari Manoogian, a former state representative in Michigan who succeeded Mr. Wahls as the executive director of the Next 50, a group that aims to lift rising Democrats, sounded a hopeful note.
“I’ve knocked doors in Iowa City, and I’ve knocked doors in Cedar Rapids,” Ms. Manoogian said. “I was expecting to see lots of visibility for Josh Turek because of the amount of money that’s being spent, and I was expecting to see a physical presence or a groundswell of support — and I simply haven’t seen it.”
On Tuesday, on his way out of the church after he voted, Mr. Turek ran into some neighbors of his who have known his family for decades.
“This man wheeled up our hill I don’t know how many times,” Marilyn Kennedy said of Mr. Turek’s canvassing efforts.
She said she and her husband, Rob Kennedy, voted for him in 2022 for the state House, in 2024 and again on Tuesday.
“I’ve got probably one of the steepest streets in Council Bluffs,” Mr. Kennedy said.
