Date of birth: May 27, 1946

Party: Democratic Party of Japan

Electoral district: Lower House; Hokkaido No. 3 (fifth term)

After graduating from the faculty of agriculture at the University of Tokyo, Arai entered the Agriculture, Forestry and Fisheries Ministry in 1970. A Hokkaido native, he headed the Hokkaido governor's office from 1991 until he retired from the ministry in 1993.

He was first elected to the Lower House in 1993 as a member of Japan New Party, but he left to join New Party Sakigake in 1994. He served as vice chairman of the party's policy research council when it was headed by Naoto Kan.

Arai joined the former DPJ in 1996 before the current DPJ was established in 1998. He led the party's pension project, shaping a plan to unify pension programs in 2001.

He quit the Diet in 2007 to run unsuccessfully for Hokkaido governor but made it back to the Lower House in 2009.