Date of birth: Oct. 20, 1958

Party: DPJ

Electoral district: Upper House; Chiba (first term)

Nagahama has served as deputy chief Cabinet secretary for Prime Minister Yoshihiko Noda, and was also a vice minister in the Health, Labor and Welfare Ministry in the Cabinets of Yukio Hatoyama and Naoto Kan.

A Tokyo native and Waseda University graduate, Nagahama studied at Matsushita Institute of Government and Management at the same time as Jin Matsubara, former chairman of the National Public Safety Commission.

In 1992, he assisted in the launch of the now-defunct Japan New Party, founded by former Prime Minister Morihiro Hosokawa. Around that time, Nagahama started to develop an interest in environmental issues.

He was elected to the Lower House from the former Chiba No. 4 constituency in 1993, and during his fourth term switched to the Upper House in 2007.