Upper House Election: LDP Loses Momentum in Homestretch Survey;Opposition Gains Ground in Upper House Races

By Tsuyoshi Oyabu and Kota Iga / Yomiuri Shimbun Staff Writers

16:22 JST, July 16, 2025

The ruling Liberal Democratic Party and its coalition partner Komeito have lost momentum in nearly half of the constituencies in the upcoming House of Councillors election, according to a Yomiuri Shimbun survey conducted in the final stage of the campaign, compared to one conducted at an early stage.

In the survey, the LDP lacked strength in most of the 32 decisive constituencies where only one seat is up for grabs, while opposition parties are intensifying their offensive. Meanwhile, back-and-forth struggles are taking place in constituencies where more than one seat is contested.

“We’re fighting tough across Japan. We cannot afford to lose,” Prime Minister Shigeru Ishiba said Tuesday in a speech in Kurashiki, Okayama Prefecture, listing constituencies he recently visited, such as Akita and Aomori, in each of which one seat is being contested.

Okayama is one of 10 such constituencies where the LDP is engaged in a de facto one-on-one battle with the Constitutional Democratic Party of Japan. The surveys have seen back-and-forth struggles in four of the constituencies — Okayama, Niigata, Saga and Kumamoto — from the early to late stages of the campaign. LDP candidates won in these constituencies in the 2022 upper house election, but the CDPJ sees opportunities to win this time.

On Tuesday, CDPJ leader Yoshihiko Noda urged voters in a street speech in Uonuma, Niigata Prefecture: “It is tough to win in one-seat contested constituencies. Please give us a hand.”

Noda told reporters after the speech, “There is a chance [that the ruling parties will lose their majority]. We must get hold of closely contested constituencies to make that happen.”

Among the 32 constituencies with one seat up for grabs, the LDP has been pushed back by the opposition parties all the way from the early to the final stages. Okayama is one of 14 constituencies where tight races were expected in the early-stage survey. The opposition parties had increased their lead over the LDP in seven of those constituencies in the final stage, including Fukushima, Toyama and Miyazaki. In contrast, the LDP had gained the upper hand in no constituencies.

In the early stage, the LDP had the lead in seven constituencies, but that number fell to four in the final stage when the party was challenged by Sanseito and the CDPJ in the LDP’s strongholds of Gunma and Gifu and by the Democratic Party for the People in Nara, turning those races into close contests. The LDP has managed to keep the race even in the Miyagi, Oita and Tokushima-Kochi constituencies. It will be hard for the LDP to pull off a comeback.

The LDP’s inability to consolidate its support base apparently has worked to the disadvantage of its candidates fighting in conservative strongholds such as the Kyushu and Hokuriku regions. In the one-seat contested constituencies, LDP candidates have secured only about 70% backing from the party’s own support base on average. In contrast, CDPJ candidates have secured 80%-90% from its support base in most constituencies.

Another serious factor is independent voters moving away from the LDP. In 20 constituencies where one seat is contested, or about 60% of such constituencies, LDP candidates have secured less than 10% of independent voters’ support. In contrast, the CDPJ has secured more than 20% in 12 of the 17 constituencies where the party fielded an official candidate.

“The situation will become even more challenging if we take into account undecided voters,” a former cabinet minister from the LDP said.

Itsunori Onodera, the chairperson of the LDP Policy Research Council, said: “Many constituencies are tied [so far]. We will continue to expand our support network until the very end.”

Pessimism has begun growing in the LDP, with one veteran member saying: “No matter what we say, it no longer resonates with voters. A historic defeat is becoming a reality.”