Candidates supported by the CDP are leading in all three Japan by-elections.

In a surprising turn of events, candidates backed by the main opposition Constitutional Democratic Party of Japan are leading the polls ahead of three crucial by-elections for the House of Representatives on Sunday.

The ruling Liberal Democratic Party has decided to field its own candidate, Norimasa Nishikori, only in the by-election in Shimane Prefecture’s No. 1 constituency. However, for the other two elections in Tokyo’s No. 15 and Nagasaki Prefecture’s No. 3 constituencies, the LDP has opted not to run candidates amidst public criticisms over their long-standing practice of creating slush funds.

In Shimane, the CDP’s former lawmaker Akiko Kamei is gaining significant support over Nishikori, a rookie aiming to succeed the seat left vacant by the late former Lower House Speaker Hiroyuki Hosoda of the LDP, in collaboration with the Japanese Communist Party.

The Tokyo election, with nine contestants in the race, sees CDP rookie Natsumi Sakai leading slightly ahead of Nippon Ishin no Kai candidate Yui Kanazawa and independent candidate Hirotada Ototake, who is favored by Tokyo Gov. Yuriko Koike. Two other rookies, Genki Sudo and Akari Iiyama, are also in the running.

The by-elections come in the wake of the resignation of former state justice minister Mito Kakizawa, a member of the LDP, who was convicted for vote-buying in a mayoral election in Tokyo’s Koto Ward.

In Nagasaki, the seat previously held by Yaichi Tanigawa is being contested by Katsuhiko Yamada, a former CDP lawmaker, and Nippon Ishin rookie Shoichiro Inoue. Yamada has garnered support from CDP and JCP backers, while Inoue is struggling with low name recognition among voters.