# Hokkaido 9th district

Hokkaidō 9th district is a constituency of the House of Representatives in the Diet of Japan (national legislature). It consists of Hokkaido's Hidaka and Iburi Subprefectures. As of 2009, 414,438 eligible voters were registered in the district.
Hokkaidō 9th district, like neighboring 8th and 10th district, was considered a "Democratic kingdom" (minshu-ōkoku), a stronghold of the Democratic Party of Japan (DPJ). From its creation in 1996 until 2012 it had been represented by DPJ co-founder Yukio Hatoyama. In 2012, Hatoyama retired. The LDP had nominated Hokkaidō prefectural assemblyman and former Olympic speed skater Manabu Horii as their candidate in July 2012.
Horii held the seat until 2021 when he was defeated by Tatsumaru Yamaoka, son of Diet member Kenji Yamaoka.
In the 2000, 2003 and 2005 general elections, the Liberal Democratic Party's candidate was Hirofumi Iwakura, later mayor of Tomakomai, Iburi Subprefecture. In 2000, Iwakura lost the district to Hatoyama by a margin of less than 3,000 votes.
Before the 1994 electoral reform, the area had been part of Hokkaido 4th district where five representatives were elected by single non-transferable vote. Yukio Hatoyama (New Party Sakigake), Tatsuo Takahashi (LDP) and Tomoko Kami (JCP) had already stood as candidates there in 1993.

## List of representatives

| Representative | Party | Dates | Notes |
| Yukio Hatoyama | DPJ | 1996 – 2012 | Prime Minister of Japan (2009–10) |
| Manabu Horii | LDP | 2012 – 2021 | Elected in Hokkaido PR block, resigned in 2024 |
| Tatsumaru Yamaoka | CDP | 2021 – | |

## Election results

2024 :
| Party | Party | Candidate | Votes | % | ±% |
| | CDP | Tatsumaru Yamaoka | 106,007 | 56.1 | 4.6 |
| | LDP | Hideki Matsushita | 62,328 | 33.0 | 15.5 |
| | JCP | Hiroshi Tatsuno | 20,557 | 10.9 | |
| Turnout | Turnout | Turnout | | 53.35 | 5.57 |
| Registered electors | Registered electors | Registered electors | 366,294 | | |
| | CDP hold | CDP hold | CDP hold | CDP hold | CDP hold |
2021 :
| Party | Party | Candidate | Votes | % | ±% |
| | CDP | Tatsumaru Yamaoka | 113,512 | 51.51 | 13.5 |
| | LDP | Manabu Horii (endorsed by Kōmeitō) (won PR seat) | 106,842 | 48.49 | 1.8 |
| Majority | Majority | Majority | | 3.02 | |
| Turnout | Turnout | Turnout | | 58.92 | 1.04 |
| | CDP gain from LDP | CDP gain from LDP | Swing | 5.8 | |
2017 Japanese general election: Hokkaido 9th :
| Party | Candidate | Votes | % |
| LDP | Manabu Horii (endorsed by Kōmeitō and New Party Daichi) | 108,747 | 46.8% |
| Kibō no Tō | Tatsumaru Yamaoka (won PR seat) | 88,320 | 38.0% |
| JCP | Chiharu Matsuhashi | 35,543 | 15.3% |
2014 Japanese general election: Hokkaido 9th :
| Party | Party | Candidate | Votes | % | ±% |
| | LDP | Manabu Horii (endorsed by Kōmeitō) | 97,805 | 45.73 | 9.46 |
| | Democratic | Tatsumaru Yamaoka | 86,252 | 40.32 | 12.25 |
| | JCP | Ryōichi Kudō | 29,841 | 13.95 | 0.62 |
| Majority | Majority | Majority | 10,653 | 5.41 | 21.71 |
| Turnout | Turnout | Turnout | | 55.19 | 2.24 |
| | LDP hold | LDP hold | Swing | 10.86 | |
2012 Japanese general election: Hokkaido 9th :
| Party | Party | Candidate | Votes | % | ±% |
| | LDP | Manabu Horii (endorsed by Kōmeitō) | 121,145 | 55.19 | 29.13 |
| | Democratic | Tatsumaru Yamaoka (endorsed by PNP) | 61,616 | 28.07 | 38.29 |
| | JCP | Yasuko Hanai | 29,257 | 13.33 | 6.70 |
| | Ainu | Naomi Shimazaki | 7,495 | 3.41 | N/A |
| Turnout | Turnout | Turnout | | 57.43 | 17.24 |
| | LDP gain from Democratic | LDP gain from Democratic | Swing | 33.7 | |
2009 Japanese general election: Hokkaido 9th :
| Party | Party | Candidate | Votes | % | ±% |
| | Democratic | Yukio Hatoyama (endorsed by PNP) | 201,461 | 66.3 | 17.0 |
| | LDP | Satoshi Kawabata (endorsed by Kōmeitō) | 79,116 | 26.1 | 16.9 |
| | JCP | Akiko Satō | 20,286 | 6.7 | 1.0 |
| | Happiness Realization | Eiichi Satomura | 2,735 | 0.9 | N/A |
| Turnout | Turnout | Turnout | 308,795 | 74.67 | 1.41 |
2005 Japanese general election: Hokkaido 9th :
| Party | Party | Candidate | Votes | % | ±% |
| | Democratic | Yukio Hatoyama | 150,050 | 49.3 | 0.7 |
| | LDP | Hirofumi Iwakura (endorsed by Kōmeitō) | 131,130 | 43.0 | 0.9 |
| | JCP | Akiko Satō | 23,400 | 7.7 | 0.2 |
| Turnout | Turnout | Turnout | 308,545 | 73.26 | |
2003 Japanese general election: Hokkaido 9th :
| Party | Candidate | Votes | % | ±% |
| Democratic | Yukio Hatoyama (endorsed by SDP) | 141,442 | 50.0 | 4.6 |
| LDP | Hirofumi Iwakura (endorsed by Kōmeitō) | 118,958 | 42.1 | 2.5 |
| JCP | Seiji Tanimoto | 22,382 | 7.9 | 2.1 |
2000 Japanese general election: Hokkaido 9th :
| Party | Candidate | Votes | % | ±% |
| Democratic | Yukio Hatoyama | 131,500 | 45.4 | 7.4 |
| LDP | Hirofumi Iwakura (endorsed by Kōmeitō, NCP) (won PR seat) | 128,975 | 44.6 | 17.1 |
| JCP | Yūichi Tazawa | 28,840 | 10.0 | 9.7 |
1996 Japanese general election: Hokkaido 9th :
| Party | Candidate | Votes | % |
| Democratic | Yukio Hatoyama | 131,936 | 52.8 |
| LDP | Tatsuo Takahashi | 68,793 | 27.5 |
| JCP | Tomoko Kami | 49,196 | 19.7 |