There is a tendency for the ruling party to benefit significantly in the proportional representation system when the Cabinet in power right before a House of Councillors election has a high approval rating.
Election results since the non-binding open list system was adopted in the 2001 upper house election show that in that year, when the Cabinet of then Prime Minister Junichiro Koizumi had an approval rating of 84 percent, the ruling Liberal Democratic Party (LDP) secured 20 seats. In the upper house election held in 2013, when the Cabinet of Prime Minister Shinzo Abe was at a 55-percent approval rate, the party secured 18 seats.
There will be 48 seats available in the proportional representation bloc in this summer's upper house election.
According to a nationwide public opinion poll conducted by the Mainichi Shimbun, the Abe Cabinet's approval rating was at 43 percent as of December last year, and is on an upward swing. Yet, it is also true that upper house elections that do not entail a change in administrations tend to put ruling parties at a disadvantage. For example, the 1989 election that took place following the Recruit corruption scandal and the implementation of the consumption tax resulted in the then Japan Socialist Party making leaps and bounds, and ending the LDP majority in the upper house.
The LDP has decided on 22 proportional representation candidates, the core of which comprises members of powerful organizations such as a national association of postmasters and the All-Japan Agricultural Policy League. While such organizations do not have the vote-drawing power that they once did, the LDP is set to take the traditional route of relying on organized support.
The party has also begun to pour efforts into attracting younger voters. For example, it has launched an "Internet election" in which even non-party members can vote for proportional representation candidates chosen from among party member and non-party member applicants. According to the LDP, some 110 people between their 30s and 70s had applied to become proportional representative candidates by the end of last year. The number was narrowed down to around 10; an "election" will be held in April to choose a final candidate.
Thus far, the main opposition Democratic Party of Japan (DPJ) has officially endorsed 18 proportional representation candidates, including members of labor unions affiliated with the Japanese Trade Union Confederation (Rengo). In the previous upper house election in 2013, the DPJ officially endorsed 20 candidates, and took a record low seven seats. Due to the party's current stagnation, the party is set to narrow down its candidate numbers to about the same as last time.
The Japanese Communist Party (JCP) is to put up eight proportional representation candidates. In recent national elections, the JCP has increased its presence, serving as an outlet for those who object to the Abe administration. This has prompted concern among other opposition parties that the JCP may once again be the only opposition force to make major gains in the upcoming election. The JCP is trying to expand its support base by focusing its energies on disaffected young people enduring poor working conditions.
Meanwhile, the Japan Innovation Party is officially endorsing four incumbent lawmakers whose terms are ending in the next election as proportional representation candidates, but has yet to come up with additional candidates. The Social Democratic Party is desperate to maintain the number of seats they currently have, with both party chief Tadatomo Yoshida's and previous party chief Mizuho Fukushima's terms coming to an end.