Peltola, a former state lawmaker, was the winner according to the Alaska Division of Elections. She defeated Palin by three percentage points at 51.47 percent; Palin received 48.53 percent.
Peltola will finish the remainder of the term of Republican Rep. Don Young (R-Alaska), which expires at the end of this year. Young left the seat vacant when he died in March this year at the age of 88.
Peltola will later face re-election on Nov. 8. Palin and Republican Nick Begich III are expected to vie for the House seat for the next two years.
The election marked the first time the state used a ranked-choice system where voters list candidates in order of preference on the ballot. To be declared the winner, a candidate must clear 50 percent of the vote.
She is the first Alaska Native to represent a state where almost 20 percent of the population is indigenous, the highest proportion in the United States. She will also be the first woman to hold the seat. Young had held the seat for 49 years and became the longest-serving Republican in the history of the House.
During her campaign, Peltola ran as “Alaska’s best shot at keeping an extremist from winning,” according to her campaign website. She also said she was “the only candidate in this race who isn’t a multi-millionaire.”
Palin’s campaign for the House seat was her first run for public office after she was tapped by John McCain as his running mate in the presidential election in 2008. The two lost to then-presidential candidate Barack Obama and vice-presidential candidate Joe Biden.