The three were the most prominent candidates in a field of 12 running for the seat in Alaska's primary on Tuesday. Under Alaska's open primary system, voters were asked to pick one candidate, with the top four vote-getters in the race, regardless of party affiliation, advancing to the ranked choice general election.

Tuesday's primary helps set the stage for what is expected to be a hotly contested and closely watched race in November. Republicans are hoping to reclaim the seat, which Republican U.S. Rep. Don Young held for 49 years before his death in 2022. Peltola became the first Alaska Native elected to Congress with her wins in special and regular elections that year.

Begich, who ran unsuccessfully for the seat in 2022, is running with support from a number of local Republican groups. Dahlstrom was endorsed by former President Donald Trump.

Begich had said he would withdraw from the race if he finished behind Dahlstrom. Dahlstrom did not make a similar pledge.

THIS IS A BREAKING NEWS UPDATE. AP's earlier story follows below.

JUNEAU, Alaska (AP) -- Alaska U.S. Rep. Mary Peltola catapulted to office in 2022 with a campaign that emphasized civility in politics. She became the first Alaska Native in Congress and the first Democrat in 50 years to hold the state's only House seat.

But in her reelection bid, she is finding some of the pitfalls of playing the middle in today's polarized political landscape.

Weeks before Tuesday's primary, she faced backlash on social media after telling reporters she was "keeping an open mind" about the presidential race and declining to endorse presumptive Democratic nominee Kamala Harris. She was forced to clarify that she would not, in fact, vote for former President Donald Trump.

She further angered some supporters when she voted with Republicans on a resolution condemning the role of Harris, the vice president, in the Biden administration's handling of the U.S. border with Mexico.

"On the president, my opinion doesn't matter at all," Peltola told The Associated Press. "We are not a swing state; we're very, very far away from being anywhere close to a swing state. So for people to demand a certain reaction, it's a waste of energy." She said she would not be endorsing anyone.

The primary -- in which Peltola faces 11 challengers, including Republicans Nick Begich and Nancy Dahlstrom, who is the lieutenant governor and has been endorsed by Trump -- will set the stage for what's expected to be a hotly contested race in November that could help decide control of the U.S. House. Under Alaska's open primary system, the top four vote-getters advance to the ranked choice general election.

Only the frontrunners -- Peltola, Dahlstrom and Begich -- have reported raising money.

So far, the pace of this year's race is a sharp contrast to the mad scramble two years ago sparked by the death of Republican U.S. Rep. Don Young, who'd held Alaska's House seat for 49 years. Nearly 50 candidates, including 2008 GOP vice presidential nominee Sarah Palin, ran in a special primary seeking to replace him.

Peltola, who is Yup'ik and is a former state lawmaker from a rural community, went on to win the special general election to serve the remainder of Young's term and later won a full term, casting herself as a consensus builder and running on a platform of "fish, family and freedom."

That year also was the debut of Alaska's voter-approved open primary and ranked choice general election system. Supporters and critics of the system alike cite Peltola's success for why they either think it's working or that it should be scrapped.

Backers of ranked voting say it provides voters more choice and rewards candidates who appeal to a broader portion of the electorate. Opponents say it's confusing and pushes voters to rank candidates they don't support.

Most polling locations opened on time Tuesday, but several did not open until around 10 a.m., and one in Anaktuvuk Pass -- an Alaska Native community of about 400 in the central Brooks Range in northern Alaska -- did not open until around 7:30 p.m., roughly a half hour before polls closed at 8 p.m., Division of Elections Director Carol Beecher said by email. Polling sites in the Alaska Native villages of Wales and Kaktovik had not opened, she said.

"Despite trying multiple ways to contact the poll workers, the individuals we had hired for those communities were unresponsive today," Beecher said. Elections officials were able to connect with the mayor of Anaktuvuk Pass to open a location there, she said.

The polling location in another community, Kobuk, a village of about 160 people, opened in the morning but closed early due to flooding in the region, she said.

In the 2022 primary, 43 people voted in Kaktovik, which lies within the Arctic National Wildlife Refuge, and 10 voted in Wales, about 110 miles (177 kilometers) northwest of Nome in western Alaska, the Anchorage Daily News reported.

Begich, a businessman who finished behind Peltola and Palin in 2022, is running with support from numerous local Republican groups, while Dahlstrom has the backing of House Speaker Mike Johnson and other prominent House Republicans.

In endorsing Dahlstrom, Trump blamed Begich for Republicans losing in 2022, a year when Begich sniped at Palin, and Trump and Palin criticized ranked choice voting -- with Trump calling it a "rigged deal."

Begich is from a family of prominent Democrats, including his late grandfather, who held the House seat before Young. Begich said he will withdraw if he finishes behind Dahlstrom on Tuesday, casting his pledge as a way to drive Republican interest in the primary. He also said having more than one Republican in the race in November could undercut GOP efforts to reclaim the seat.

Dahlstrom hasn't made the same commitment but said once the results are in, she wants to talk with Begich, Republican Gov. Mike Dunleavy and the head of the state Republican party to analyze "who got what and what it's going to take to have a conservative in that seat vote-wise."

The majority of registered voters in Alaska aren't affiliated with a party, a fact Peltola cites in explaining why she's not making endorsements.

"I just think it's important for people to make up their own mind," she said. The last time Alaska went for a Democratic presidential nominee was 1964.

At a recent Peltola campaign event in Juneau, Democratic voter Kiernan Riley, a member of the LGBTQ community, waited as Peltola made the rounds so they could ask about Trump. Riley said they find Trump's positions offensive.

While Riley said they didn't need Peltola to endorse Harris, they did want to know her position on Trump before deciding whether to hang a large Peltola campaign sign on their fence.

Riley said hearing from Peltola directly made them feel better.

"I understand the complexities of being a Democrat in a red state," Riley said.