Japanese Prime Minister Fumio Kishida's ruling bloc on Sunday won key gubernatorial elections, with its candidates defeating their rivals backed by the leading opposition party in the first round of nationwide local polls.

The victories, such as that of Naomichi Suzuki, the incumbent governor of Japan's northernmost main island of Hokkaido, may bode well for Kishida and his Liberal Democratic Party amid speculation that he could dissolve the lower house for a snap election at an early date.

In Oita Prefecture, Kiichiro Sato, supported by the LDP, and Kiyoshi Adachi were in a close battle. Adachi won his parliamentary seat in 2019 with the backing of the main opposition Constitutional Democratic Party of Japan. But Sato, a former mayor of its capital city, defeated the former upper house opposition lawmaker.

The results indicated Kishida's efforts to prop up his government's popularity by making diplomatic achievements helped to some degree before he hosts a Group of Seven summit in May in his constituency of Hiroshima, political pundits said.

Incumbent Hokkaido governor Naomichi Suzuki (C) celebrates his re-election in Sapporo on April 9, 2023. (Kyodo)

Former lower house lawmaker Masazumi Gotoda, an LDP member who ran for governor of Tokukshima Prefecture as a non-affiliated candidate, defeated incumbent Gov. Kamon Iizumi, who was backed by the local chapter of the ruling party.

The LDP, however, had failed to put up its own candidates against a backdrop of a feud in the conservative party in the western prefectures of Tokushima and Nara, forcing the contenders to compete fiercely.

LDP election chief Hiroshi Moriyama told reporters following the local races, "We have to reflect on" how the ruling party coordinated its candidates, adding that the party will work closely with its regional organizations further.

Osaka Gov. Hirofumi Yoshimura, meanwhile, secured his second term, beating rivals endorsed by the LDP and other parties. He has enjoyed wide popularity as the co-leader of the Japan Innovation Party, which has its roots in the western prefecture.

In Nara, former bureaucrat Sho Hiraki, backed by the prefectural chapter of the LDP, was beaten by former local city mayor Makoto Yamashita, fielded by the opposition Japan Innovation Party, which has a strong foothold in the Kansai region, including the prefecture.

Osaka Gov. Hirofumi Yoshimura is pictured at a press conference in Osaka on April 9, 2023, after securing his second term in the western prefecture's gubernatorial election. (Kyodo)

In the other four prefectures of Kanagawa, Fukui, Tottori and Shimane, incumbent governors were jointly supported by the ruling and opposition camps. All the incumbents were re-elected.

Mayoral races in six major cities, alongside local assembly polls in 41 prefectures and 17 big cities, were also held as part of the first round of unified local elections, carried out every four years.

In the Osaka mayoral race, Hideyuki Yokoyama, backed by the Japan Innovation Party, was elected.

The other round of the quadrennial local polls, designed to cut administrative costs and raise voter turnout, will be conducted on April 23 to select mayors and assembly members in other municipalities nationwide and will coincide with by-elections for five vacant seats in parliament.

Moriyama said the LDP will "use the momentum" of Sunday's victories in the key gubernatorial elections to win the second round of the local polls and by-elections.

All eyes are on whether voters will support the government's measures to curtail the adverse effects of rising prices and its plan to boost spending for defense and child-rearing policies, which have fanned fears about possible tax increases.

The latest local elections came as approval ratings for Kishida's Cabinet have shown signs of improving, sparking rumors that the premier could dissolve the lower house in the not-so-distant future.

Under Japan's Constitution, a prime minister has the final say on the dissolution of the lower house. The current four-year terms for lower house members expire in October 2025 unless Kishida dissolves the chamber.

Kishida, who took office in October 2021, has been exploring the best timing to win a general election, as he is eager to be re-elected as leader of the ruling party. The next LDP presidential race is slated to be held in September 2024.

Media polls show that the support rate for Kishida's Cabinet has picked up recently, especially since he made an unannounced visit on March 21 to Ukraine, which was invaded by Russia more than a year ago, for talks with President Volodymyr Zelenskyy.

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