Three candidates entered the race for the leadership of Nippon Ishin no Kai on Sunday as the conservative opposition party moves to replace leader Ichiro Matsui.

The party's co-leader Nobuyuki Baba is seen as the most likely winner of the Aug. 27 election, ahead of the fellow contenders Yasushi Adachi and Mizuho Umemura.

Baba has the support of Matsui and some other senior members of the party, which advocates for constitutional reform as one of its major policy platforms.