The leadership race of the major opposition Constitutional Party of Japan (CDP) is shaping up to be a clash of old and new generations, with two veterans facing off against a younger incumbent and another younger challenger in the Sept. 23 election.

Yoshihiko Noda, 67, and Yukio Edano, 60, served as prime minister and chief Cabinet secretary, respectively, when the now-defunct Democratic Party of Japan (DPJ) was in power. In contrast, current CDP chief Kenta Izumi, 50, did not have a major presence in the DPJ, while Harumi Yoshida, 52, is only in her first term as a lawmaker.

CDP legislators can be divided into three groups — a first generation, comprised of Ichiro Ozawa and other heavyweights who led the party during its time in power; a second generation, which includes Noda, Edano and others first elected to parliament between 1993 and 2000; and a third generation, with legislators like Izumi and others who stepped into office in 2000 or after.