The US military presence will remain a major issue for Koja, a former civil servant who was also a deputy mayor of Naha, the region’s capital city.
The United States has around 54,000 military personnel stationed in Japan, mostly on Okinawa, but a string of incidents over the years, including sexual assault cases, have angered residents.
Other base-related woes, from pollution to noise and helicopter crashes, have led to further complaints.
Japan and the United States agreed to move the base from the town of Ginowan to another location within Okinawa in 1996 after a rape of a 12-year-old schoolgirl by US military servicemen that triggered strong anti-US military protests across the prefecture.
The relocation plan was approved in 2013 by Okinawa’s then governor Hirokazu Nakaima, but the next year he lost to an opponent who opposed the move.
Tamaki, 66, was seeking his third term on Sunday.
Koja won 423,124 votes, while Tamaki received 276,060, according to the prefectural government.
