TOKYO (Reuters) - A candidate backed by Japanese Prime Minister Shinzo Abe’s ruling coalition defeated an incumbent mayor opposed to a U.S. Marines base on Okinawa in an election on Sunday, NHK public TV and other domestic media reported.

The victory could give impetus to a long-stalled, controversial plan to relocate the U.S. Marines’ Futenma air base from an urban area in central Okinawa to the less populated Henoko district of the northern city of Nago.

Japan’s central government and authorities on Okinawa - reluctant host to the bulk of U.S. military forces in the country - have bickered for years over the plan, first agreed between Tokyo and Washington in 1996.

Defeated Nago Mayor Susumu Inamine and Okinawa Governor Takeshi Onaga are among the opponents of the move, who want to have Futenma’s functions moved off Okinawa entirely.

Abe’s government wants to forge ahead with the relocation.

Inamine, who was seeking a third four-year term with

opposition parties’ support, was defeated by Taketoyo Toguchi, backed by Abe’s Liberal Democratic Party (LDP) and its junior coalition partner, the Komeito party.

NHK said that Toguchi - whose platform focused on improving the local economy - won 20,389 votes to Inamine’s 16,931.

A win for Toguchi will make it easier for Abe’s government

to carry through the relocation. Work is underway for construction of a Futenma replacement facility, but some aspects require approval from the Nago mayor.

Many Okinawa residents have long associated the U.S. military presence with crime, pollution and accidents, and resentment was rekindled by a spate of incidents involving U.S. military aircraft. In December, a window fell from a U.S. helicopter onto a school sports field, fanning safety concerns.

Toguchi’s victory, however, could bode ill for Okinawa Governor Onaga, who is up for re-election late this year, media said.