HONOLULU (AP) — In a stunning defeat for an incumbent, Hawaii Gov. Neil Abercrombie was unseated by a fellow Democrat in Saturday's primary election, as Democratic voters chose state Sen. David Ige as their nominee in one of two marquee races that have divided the party.

Abercrombie had tried to hold onto his seat while disgruntled voters turned their allegiance to Ige, who promised to bring a less confrontational political style. Voters rewarded Ige with a decisive victory Saturday.

In the U.S. Senate race, incumbent Democrat Brian Schatz also faces a threat from fellow Democrat U.S. Rep. Colleen Hanabusa, who believes the seat should have been passed on to her when her mentor, U.S. Sen. Daniel Inouye, died in 2012.

Hanabusa took a slight lead over Schatz with 49 percent compared with 47 percent for Schatz in early returns Saturday night, based on 104,000 votes cast early or absentee.

The winners of each race will face Republicans and independent candidates in the November general election, but such campaigns are often longshots in heavily Democratic Hawaii.

Ige mounted his challenge against Abercrombie despite being outspent by about 10 to 1. While Abercrombie tore through $4.9 million through July 25, Ige spent just $447,000, according to Hawaii's Campaign Spending Commission.

Challenging the incumbent Democrat may have hurt Ige's ability to fundraise. But Ige, a respected state senator who served in the Legislature for 28 years, felt Hawaii was headed in the wrong direction, and that too many of the governor's decisions were dividing communities, he said.

"There were many in the party that did not want me to run," Ige said in a recent interview. "They felt like the incumbent should be supported."

As the final days of campaigning drew to a close, a pair of big storms thrashed toward the islands, presenting an opportunity for Abercrombie to show a strong emotional connection to voters. His calm demeanor as Tropical Storm Iselle thrust through the islands was a contrast to his usual style.

But many Ige voters said they weren't necessarily taken in by Ige — they just didn't like Abercrombie. Some cited disappointment with the way Abercrombie handled contract negotiations with teachers and his past support for a plan to tax pensions.

"There's been so much friction between Abercrombie, the Legislature and communities," said Tom White, 62, who's retired from the U.S. Navy and voted for Ige Saturday. "He's too many rough edges."