The Alaska U.S. Senate race remains undecided after Election Day and will proceed to ranked-choice voting tabulation next week.

Unofficial results show Democrat Mary Peltola leading incumbent Republican Sen. Dan Sullivan by 637 votes. Peltola has 102,962 votes, or 48.2 percent, while Sullivan has 102,325 votes, or 47.9 percent. Two other candidates split additional support, with Republican Gerald Heikes at 4,846 votes and Daniel J. Sullivan Jr. at 3,600 votes.

Neither major candidate reached a majority of first-choice votes, triggering the state's ranked-choice process. Officials will conduct the tabulation on November 18 after all ballots are counted.

The two lower-polling candidates, both Republicans, drew more than 8,400 votes combined. Reports indicate Democratic-aligned efforts helped recruit or fund these candidacies to draw votes from Sullivan.

Additional mail and absentee ballots, which tend to favor Democrats, remain to be tallied. Analysts from multiple outlets project Peltola could extend her lead once those are included.

A New York Times review of available ranked-choice data found Sullivan would gain only about 0.4 percentage points from the redistribution of ballots cast for the eliminated candidates. That shift would fall short of overcoming Peltola's current margin.

The race marks one of the most expensive Senate contests in Alaska history, with total spending exceeding $150 million. Sullivan has held the seat since 2015. Peltola previously won the state's at-large House seat in a 2022 special election.

Final certification is scheduled for November 25. The outcome could influence the balance of power in the U.S. Senate.