OLYMPIA, Wash. (AP) — The two Republican members of Congress from Washington who drew interparty challenges due to their vote to impeach former President Donald Trump were leading other Republicans in the state’s top two primary Wednesday.

Under Washington’s primary system, all candidates run on the same ballot, and the top two vote getters in each of Tuesday’s races advance to the November election, regardless of party — a system observers say may have helped the GOP incumbents in Washington who had been targeted by Trump.

In early returns, Reps. Jaime Herrera Beutler and Dan Newhouse looked as they may advance to the general election with a Democratic candidate in each of their races. Trump-endorsed candidates in both races were in third place.

Because Washington is a vote-by-mail state and ballots just need to be in by Election Day, it can take days to learn final results as ballots arrive at county election offices throughout the week.

Of the 10 House Republicans who voted for impeachment following the Jan. 6 attack on the U.S. Capitol, four opted not to run for reelection. Michigan Rep. Peter Meijer was defeated in a primary Tuesday by Trump-endorsed John Gibbs and Rep. Tom Rice of South Carolina lost to a Trump-endorsed challenger in June. Rep. David Valadao of California — which has an open primary like Washington — survived a primary challenge. Rep. Liz Cheney of Wyoming is bracing for defeat in her Aug. 16 primary against a Trump-backed rival.

If Herrera Beutler and Newhouse ultimately advance to the general election ballot as Valadao did, it will be in large part due to the mechanics of the top two primary, said Cornell Clayton, director of the Thomas S. Foley Institute for Public Policy at Washington State University.

“The top two primary is designed to favor more moderate candidates and make it more difficult for the extremes in either party to primary moderate candidates,” he said.

The number of Republican candidates in these particular two races gave an advantage to Democrats’ chances in claiming one of the top two spots, leaving the Republican vote split, Clayton notes. Herrera Beutler faced eight opponents, half of whom are Republicans, and Newhouse faced seven, including six Republicans.

“There is a slight incumbent advantage among those Republicans,” Clayton said.

Herrera Beutler, who represents the 3rd Congressional District in the southwestern part of the state, had about 25% of the vote Tuesday night, and Democrat Marie Gluesenkamp Perez captured nearly 32%. Joe Kent – a former Green Beret endorsed by Trump who faced significant spending against him from another Republican who attacked him from the right – was at 20%.

“Right now, I am focused on making sure not to get out over my skis,” Herrera Beutler, who is seeking her seventh term, said in a Zoom news conference with reporters Tuesday night. “I’m excited about the numbers but we’re not done yet, we still have more votes to count.”

Kent Tweeted Wednesday that dozens of precincts haven’t reported their tallies yet and that “there’s still a pathway.”

Rep. Dan Newhouse, the four-term incumbent in the 4th Congressional District in central Washington, had just over 27% of the vote in early returns, followed by Democrat Doug White, who had about 26%. Loren Culp, a Trump-endorsed former small town police chief who lost the 2020 governor’s race to Democrat Jay Inslee, was just under 22%.

Culp noted on Facebook that the difference between first and third place is a difference of just over 4,100 votes.

“The race is tight and more than half of the vote is still out!” he wrote.

Counties in both districts are expected to update their tallies later Wednesday afternoon and evening, and most counties will post updates daily until all of the votes are counted.