Six States Vote June 2: An Open Iowa Senate Seat, California's First Test of the Prop 50 Map, and Two Wide-Open Governor Primaries

Tuesday, June 2, 2026 is the second six-state primary day of the cycle. Iowa picks a replacement for retiring Senator Joni Ernst. California holds its first congressional primary on the redrawn Prop 50 map, plus a special election for the CA-1 seat held by Doug LaMalfa, who died in January. Montana's Senate seat is open after Steve Daines withdrew in March. New Mexico, New Jersey, and South Dakota fill out the night.

Below is what's on each state's ballot.

Iowa: the open Ernst seat and two Toss-up House races

Polls are open 7 a.m. to 8 p.m. Central Time. Joni Ernst is retiring after two terms. The Republican primary for her seat is the marquee race of the night, with congresswoman Ashley Hinson leading the field after withdrawing from her IA-2 reelection bid. Cook rates the seat Likely Republican for November.

Iowa also has the two Toss-up House races on the June 2 calendar. IA-1 has Democrat Christina Bohannan challenging Republican incumbent Mariannette Miller-Meeks. IA-3 has Republican incumbent Zach Nunn defending against a contested Democratic primary led by Sarah Trone Garriott.

IA-2 is now open after Hinson's Senate run. The Republican gubernatorial primary is also contested, with congressman Randy Feenstra running for the seat after term-limited Republican Kim Reynolds declined a fourth bid. The general election is rated Lean R. Find your district at the Iowa ballot lookup.

California: 52 House primaries on the new map

Polls close at 8 p.m. Pacific Time. California runs a top-two primary, meaning every candidate from every party appears on a single ballot, and the top two vote-getters advance to November regardless of party. It also runs a vote-by-mail election with same-day registration.

This is the first congressional primary on California's redrawn map. Voters approved Proposition 50 in November 2025, which gave the legislature emergency authority to redraw lines. Twelve-term Republican Darrell Issa announced his retirement on March 6 rather than run on the new lines.

The night also includes a special election in CA-1, the seat held by Republican Doug LaMalfa, who died in January. The special is on the same ballot as the regular primary. If no candidate clears 50 percent, an August 4 runoff will decide it. The seat is rated Safe Republican.

The only Toss-up House race is CA-22, where Republican David Valadao is defending against a contested Democratic primary led by state assemblywoman Jasmeet Bains and Visalia school board member Randy Villegas. CA-45 has freshman Democrat Derek Tran defending. CA-13 in the Central Valley has freshman Democrat Adam Gray defending. CA-48, open after Issa's retirement, has Republican Jim Desmond facing a contested Democratic primary. All three are rated Lean Democratic.

Several other House seats are open after retirements: CA-11 (Nancy Pelosi), CA-26 (Julia Brownley), and CA-14 (Eric Swalwell, who left the seat to run for governor). All three are rated Safe Democratic.

The California governor's race is rated Safe Democratic. The race is open because Gavin Newsom is term-limited. The Democratic field includes former HHS Secretary Xavier Becerra, former Congresswoman Katie Porter, former Los Angeles mayor Antonio Villaraigosa, and billionaire Tom Steyer. Republican Riverside County Sheriff Chad Bianco leads the Republican side. Find your district at the California ballot lookup.

Montana: an open Senate seat and an open House seat

Polls are open 7 a.m. to 8 p.m. Mountain Time. Republican Senator Steve Daines withdrew from his reelection bid on March 4. Former U.S. Attorney for Montana Kurt Alme filed before the deadline closed. Cook rates the seat Lean Republican.

MT-1 is also open. Republican Ryan Zinke announced his retirement on March 2, citing health. The Republican primary to replace him is contested. The Democratic primary is led by Ryan Busse. Cook rates MT-1 Likely R.

New Jersey: NJ-7 sets up the Toss-up matchup

Polls are open 6 a.m. to 8 p.m. Eastern Time. New Jersey is a closed primary state, meaning only voters registered with a party can vote in that party's primary. Senator Cory Booker is seeking a third full term in a Safe Democratic race.

The competitive House race is NJ-7, rated Toss-up. Republican Tom Kean Jr. is defending against a contested Democratic primary.

NJ-12 is an open seat after Bonnie Watson Coleman announced in November that she would not seek a seventh term. The Democratic primary is contested. The seat is rated Safe Democratic. Find your district at the New Jersey ballot lookup.

New Mexico: Haaland vs. Bregman for an open governorship

Polls are open 7 a.m. to 7 p.m. Mountain Time. Democratic Governor Michelle Lujan Grisham is term-limited. The Democratic primary to succeed her is the headline race between former Interior Secretary Deb Haaland and Bernalillo County District Attorney Sam Bregman. The general election is rated Likely Democratic. The Republican primary is also contested.

Senator Ben Ray Luján is seeking a second term in a Safe Democratic race. NM-2, the only competitive House district, has freshman Democrat Gabe Vasquez defending. Find your district at the New Mexico ballot lookup.

South Dakota: a contested Republican governor primary

Polls are open 7 a.m. to 7 p.m. local time (most of the state is Central; the western counties are Mountain). South Dakota uses a runoff system for the governor's race only: if no candidate clears 35 percent, the top two return for a July 28 runoff.

The Republican primary for governor includes sitting governor Larry Rhoden, who became governor in January 2025 when Kristi Noem left to run the Department of Homeland Security, and four-term U.S. Representative Dusty Johnson, who withdrew from his House reelection to enter the race. Businessman Toby Doeden and state House Speaker Jon Hansen are also running. The seat is rated Safe Republican.

SD's at-large House seat, which Dusty Johnson vacated, is also an open Republican primary. Senator Mike Rounds is seeking a third term. Both are rated Safe R.

Before you go: rules to know

Primary rules vary by state. A few things worth knowing for June 2:

• Closed primaries. New Jersey and South Dakota's Republican primary are closed. Only voters registered with the party may vote on that party's ballot, and the registration deadline has passed in both states.
• Semi-closed primaries. Iowa and New Mexico let registered party voters vote, and let unaffiliated voters affiliate at the polling place and then vote. South Dakota Democrats also allow unaffiliated voters.
• Top-two primary. California uses a single ballot for all candidates regardless of party. Any registered voter can vote on any race. The top two finishers advance to November.
• Vote-by-mail. California runs an all-mail election with ballots mailed automatically to every registered voter. Same-day registration is available in person. Mailed ballots must be postmarked by June 2 and received by June 9.
• Bring ID. Every state on the June 2 ballot requires some form of identification at the polls. We covered the specifics in what to bring on Election Day.
• Provisional ballots. If your name is missing from the rolls, the machine rejects your ID, or you are told you are at the wrong polling place, ask for a provisional ballot. You have a legal right to one. It will be reviewed and counted if you were eligible to vote.
• For your federal picks, you can mark your Senate, House, and governor selections ahead of time with a My Ballot account and pull them up on your phone in line. For state legislative races, judges, school board, and county offices, your county clerk's sample ballot is the source of truth.

Not voting on June 2?

The next primary day is Tuesday, June 9, when Maine, Nevada, North Dakota, and South Carolina vote. Maine's Senate primary will pick a Democrat to face Republican Susan Collins in November. The full list of primary dates is on the election calendar.

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