September 2012 Democratic Party of Japan leadership election

The September 2012 Democratic Party of Japan leadership election was held on 21 September 2012. The election in accordance with the end of the presidential term which had commenced in 2010. Incumbent president and Prime Minister Yoshihiko Noda was comfortably re-elected, defeating three opponents.^[1][2]

Noda became Prime Minister in August 2011. Among his flagship policies was a plan to raise the consumption tax from 5% to 10%, which was fiercely opposed by a group of party members led by Ichirō Ozawa and Yukio Hatoyama, who threatened to split the party over the issue. A week after the passage of the bill through the lower house in late June, Ozawa and 49 other DPJ Diet members resigned from the party.^[3] A month later, on 10 August, Noda secured agreement from the opposition Liberal Democratic Party and Komeito for the bill's passage through the upper house. Ozawa and other minor parties called a motion of no confidence against Noda in the lower house the same day, which was defeated 246–86, with the LDP and Komeito abstaining.^[4] Facing a continuing string of defections, pressure to call an election, and with an approval rating under 30%, Noda faced re-election the following month.

The election was conducted via a points system:

• Each of the party's members of the National Diet had a vote worth two points. (650 points total)
• Registered party members or supporters could vote via mail. Points for this tier were distributed between the 47 prefectures, and awarded to candidates in proportion to votes won in each prefecture. (409 points total)
• Each of the party's members of local councils or prefectural assemblies could vote via mail. Points for this tier were awarded to candidates in proportion to votes won. (141 points total)
• Each of the party's approved candidates for future Diet elections had a vote worth one point. (8 points total)

In order to win, a candidate must secure more than 50% of points. If no candidate won more than 50%, a runoff was to be held the same day. In the runoff, only Diet members and approved candidates could vote.

• Sumio Mabuchi, member of the House of Representatives (2003–) and Minister of Land, Infrastructure, Transport and Tourism (2010–11)
• Mitsuru Sakurai, member of the House of Councillors (1998–)
• Masahiko Yamada, member of the House of Representatives (1993–96; 2000–) and Minister of Agriculture, Forestry and Fisheries (2010)

• Goshi Hosono, member of the House of Representatives (2000–) and Minister of the Environment (2011–)
• Seiji Maehara, member of the House of Representatives (1993–) and Minister for Foreign Affairs (2010–11) – (endorsed Noda)
• Katsuya Okada, member of the House of Representatives (1990–) and Deputy Prime Minister (2012–) – (endorsed Noda)
• Makiko Tanaka, member of the House of Representatives (1993–2002; 2003–) and chair of the Diet Foreign Affairs Committee (2011–) – (endorsed Noda)

Following Ozawa's secession, senior party leaders sought to reinforce Noda's leadership to avoid further damage. Secretary-general Azuma Koshiishi, policy chief Seiji Maehara, foreign minister Kōichirō Genba,^[5][6] and deputy Prime Minister Katsuya Okada all called for his re-election.^[7] Commentators judged that, between Maehara's support and the departure of many of the "anti-mainstream" members with Ozawa, Noda's re-election was close to assured.^[6]

The scattered anti-Noda groups struggled to find a viable candidate. In early September, there was a strong movement to draft environment minister Goshi Hosono to challenge Noda. At 41 and with little cabinet experience, he was considered a fresh face who some believed stood a better chance of winning a general election than Noda.^[8][9] Key supporters included Junya Ogawa from the Maehara faction, Takeshi Shina formerly from the Ozawa faction, Keisuke Tsumura from the Kan faction, and Shinji Tarutoko from the Kano faction.^[10] He initially denied any interest in standing,^[6][11] but as nominations approached he said on the 5th would have to "seriously consider it".^[10] He met with Noda on the 7th and informed him that he would not run after all.^[12]

With no unified anti-Noda candidate, three leaders of "anti-mainstream" factions ran independently. Michihiko Kano was supported by his own faction, Hirotaka Akamatsu by former JSP members, and Kazuhiro Haraguchi by remnants of the Ozawa faction.^[12]

A Sankei Shimbun and Fuji News Network theoretical poll at the start of September found Maehara was the most popular candidate among the public with 18% support. Prime Minister Noda was a close second with 16.1%. Katsuya Okada polled 13.4% and Hosono 3%. Among DPJ supporters, Noda placed first with 31.1%.^[13]

Sumio Mabuchi, last-place finisher in the 2011 contest, intended to run but withdrew on 8 September citing the need to unify anti-Noda forces. Mitsuru Sakurai announced on the same day that he was withdrawing due to inability to gather the twenty nominations required to stand.^[14] A group of about ten Diet members launched a campaign to support Makiko Tanaka under the name "Group to Produce a Female Prime Minister",^[15] but she stated she would not run and endorsed Noda.^[16]

• "2012 Democratic Party Presidential Election". Democratic Party of Japan (in Japanese). Retrieved 2 October 2025.