Official campaigning for quadrennial unified local elections started across Japan on Thursday, with the results likely to determine whether Prime Minister Fumio Kishida will decide to dissolve the lower house for a snap general election amid sluggish support ratings.

Incumbents and newcomers filed their candidacies for gubernatorial elections in nine prefectures, scheduled for April 9, as part of the first round of a series of local elections.

Photo taken March 22, 2023, shows a banner announcing the April 9 local elections in Oita, southwestern Japan. (Kyodo)

Mayoral races in six major cities, alongside local assembly elections in 41 prefectures and 17 big cities are slated to be held on the same day, with campaigning set to begin later this month.

Key issues expected to be raised during the 985 regional elections next month are a planned tax rise by the Kishida administration to fund an increase in defense spending, proposed steps to tackle the declining birthrate, rising costs and other regional concerns.

On Thursday, Toshimitsu Motegi, secretary general of the ruling Liberal Democratic Party, said at a kickoff ceremony in Oita Prefecture, "We will work to develop local areas and to promote regional business."

Natsuo Yamaguchi, leader of the LDP's junior coalition partner Komeito, called at a party meeting for unity to achieve victory for its candidates.

Kenta Izumi, head of the main opposition Constitutional Democratic Party of Japan, said in a stump speech near Tokyo, "We will try to create local councils that ensure diversity and reflect various voices," adding, "Let's change politics together."

The unified local elections are held simultaneously every four years to cut administrative costs and raise voter turnout.

Unless Kishida decides to dissolve the House of Representatives, this year's regional polls will be the most significant until the House of Councillors election, scheduled for summer in 2025. The current four-year terms for lower house members expire in October 2025.

Speculation has been rife that the prime minister may dissolve the powerful lower chamber and call a general election before his stint as leader of the LDP ends in September 2024, in a bid to prevent other candidates from running and secure himself a second term.

While the approval ratings for Kishida's Cabinet have remained low, his LDP aims to secure more than half of the 2,260 seats to be contested in the prefectural assembly elections.

If the ruling party fails to meet its target, however, Kishida's political clout will likely be further weakened, making seeking a mandate through a national election more difficult.

A recent Kyodo News poll showed this month the approval rating for the Cabinet stood at 38.1 percent, up from 33.6 percent in mid-February.

Among the nine gubernatorial polls, candidates supported by the ruling coalition and the opposition parties in parliament will face off in Hokkaido, Osaka, Nara and Oita.

In Kanagawa, Fukui, Tottori and Shimane, incumbents backed by both the ruling bloc and some opposition forces will compete with candidates who are fielded by the Japanese Communist Party or are standing as independents.

Meanwhile, the LDP failed to gather support for single candidates in Nara and Tokushima, in a move set to trigger a feud within its local chapters and split the votes of the party's supporters.

The second round of unified local elections to select mayors and assembly members of Tokyo's wards, smaller cities, towns and villages nationwide will be held on April 23.

By-elections for lower house seats in the Chiba No. 5 district, the Wakayama No. 1 district, and the Yamaguchi Nos. 2 and 4 districts, alongside an upper house seat in Oita Prefecture, will all be carried out on the same day.