Genta Koja, the candidate backed by Japanese Prime Minister Sanae Takaichi's Liberal Democratic Party (LDP), won Sunday's gubernatorial election in Okinawa prefecture, public broadcaster NHK reported.

The election, widely described by Japanese media as a contest between "conservative and reformist" forces, drew significant domestic attention. Six candidates ran in the election, but public attention centered mainly on Koja and incumbent Okinawa Governor Denny Tamaki.

Koja, 42, a former deputy mayor of Naha city, was backed by conservative forces including the LDP, the Japan Innovation Party, the Democratic Party for the People, and the ultraconservative Sanseito party. Tamaki, meanwhile, was supported by left-leaning forces including the Constitutional Democratic Party of Japan, the Japanese Communist Party, and the Social Democratic Party.

The contentious relocation of a key US military base in the southern Japanese island prefecture was one of the focal issues in the election.

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According to Japan's Mainichi Shimbun, Tamaki opposed the transfer of US Marine Corps Air Station Futenma from Ginowan city to the coastal Henoko area in Nago city within Okinawa. He also called for the Japanese government not to further expand the deployment of Self-Defense Forces on the country's southwestern islands and opposed joint military exercises between Japan and the United States, the newspaper said.

Koja, by contrast, supported the existing relocation plan and advocated stronger coordination and cooperation with the central government.

Okinawa residents have long suffered from problems associated with the US military presence in the prefecture, including aircraft noise, safety incidents, and crime.

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The Futenma relocation plan is based on a 1996 agreement between the Japanese and US governments and requires land reclamation and the construction of a new runway. Okinawa residents have long and firmly opposed relocating the base within the prefecture, demanding instead that it be removed from Okinawa altogether.

Takeshi Onaga, former Okinawa governor elected in 2014, explicitly opposed the base relocation, a stance maintained by his successor, Tamaki.

Japanese media said Koja's victory means that the Okinawa prefectural government will shift, for the first time in 12 years, toward supporting the Futenma base's relocation to Henoko, and that the Japanese government will move ahead with the controversial project while giving Okinawa a greater role in its push for military expansion in the southwestern islands under the pretext of "responding to challenges."