In late November, Osaka held gubernatorial and mayoral elections, and a newly reorganized, locally based party, Osaka Ishin no Kai, won both races by defeating candidates backed by the Liberal Democratic Party, the current dominant party of the national government. Incumbent Gov. Ichiro Matsui achieved an overwhelming victory over the challengers and secured a second term. As for the mayoral office, Hirofumi Yoshimura, a former member of the Lower House and hand-picked successor of incumbent Mayor Toru Hashimoto, also won by a wide margin. Throughout the races, the soon-to-retire Hashimoto committed to the campaign actively as party leader.

The major issue contested in the elections was the so-called Osaka Metropolis Plan, which aims to restructure existing prefectural and municipal administrations, eventually transforming the prefecture into another metropolis like Tokyo. The plan had been the core policy of Osaka Ishin's current members, although part of it had been rejected by a municipal referendum held in May 2015. The main focus of the elections, therefore, was this local agenda: whether or not to pursue the plan further under Osaka Ishin's governorship and mayorship, with the understanding that this result could greatly influence politics not only in Osaka but also throughout the national political landscape, particularly in the realm of national security.

These two races were crucial for Osaka Ishin's future survival and Hashimoto's potential influence in the national political arena. Besides the recent rejection of part of the Osaka Metropolis Plan by referendum, Osaka Ishin's split from the Ishin no To (Japan Innovation Party) just a month before the elections could have worked against Osaka Ishin's popularity. Therefore, this double victory was all the more critical to the party and Hashimoto, and it will likely revive the party and the mayor's allies in the Diet.