Leader of the Democratic Party in 2016. In 2016, the DPJ merged with
Japan Innovation Party forming the
Democratic Party. Maehara attempted to make a comeback at the leadership in the
first leadership election post-merger, but lost against former minister
Renho. Renho resigned in July 2017 after the DP suffered a bad result in the
2017 Tokyo assembly elections. A
leadership election was immediately held to select the new leader of the party. Maehara was one of the candidates contesting the election, along with former Chief Cabinet Secretary
Yukio Edano. Through his reliable support from conservative DP and former JIP members, Maehara comfortably won the leadership election with 60% of the points up for grabs. He returned as the leader of the largest opposition party almost 12 years after ascending to the post for the first time. Maehara's second stint as president was short and rocky. One of his first acts as the new president was to appoint rising-star lawmaker
Shiori Yamao as secretary-general in his new executive. Immediately after her nomination, tabloid magazine
Shukan Bunshun published an allegation of affair against Yamao. Whilst the details were inconclusive, Yamao resigned from the party less than a week after the affair was reported, widely seen as an effort to halt further decline of DP's fledgling support. Maehara also faced a potential rival in Tokyo governor
Yuriko Koike, who grew increasingly confident after her
party's landslide win in the Tokyo Assembly elections and was rumoured of planning to form a conservative national party to face Prime Minister
Shinzo Abe in the next general election. Abe called
a snap election less than three weeks to Maehara's ascension to the presidency. This threw the party into disarray, as it had not completed preparing its election platform. At the same day as Abe's election declaration, Koike finally launched a new party called
Kibō no Tō (Party of Hope). Seeing Koike's high popularity at that time as a potential asset, Maehara coordinated with Koike on DP candidates' nominations for the election. Koike agreed to endorse DP candidates and Maehara effectively disbanded the party in order to allow the candidates run under the Kibō banner. However, despite Maehara's request, Koike imposed an ideological filter that effectively barred liberal-leaning members of the DP, such as
Yukio Edano, from joining Kibō. This led Edano to form the
Constitutional Democratic Party less than three weeks before election to house liberal DP members. Maehara himself ran as independent. Koike's multiple blunders during the campaign led Kibō to fall well short of high initial expectations, becoming the second largest opposition party behind the Edano-led CDP. Maehara, whose political gamble had backfired, was under heavy pressure to resign from his position as DP president. Maehara resigned from his post and from the party on 28 October 2017, ending his tumultuous second term as leader of the Democratic Party.
DPFP and FEFA Maehara joined Kibō in November 2017. When Kibō merged with the
Democratic Party in May 2018 to form the
Democratic Party for the People (DPFP), Maehara also joined the DPFP. He became critical of party leader
Yuichiro Tamaki and his approach of collaborating with the LDP, and challenged Tamaki for the DPP leadership spot in 2023, claiming that he would focus on forming a collaborative front with other opposition parties outside of the
JCP. Following his defeat to Tamaki, he and several other DPP parliamentarians, including former Governor
Yukiko Kada, split from the group to form Free Education for All. The new party is believed to be focused on building an opposition coalition, but several difficulties have come up, including the closeness of Maehara to
Nippon Ishin no Kai, to which a
RENGO spokesman said that the Union would be forced to pull support from the new party if it is "swallowed up by Nippon Ishin". On 3 October 2024, the party merged into
Nippon Ishin no Kai, with all, but
Atsushi Suzuki, running under the Ishin banner.
Co-leader of Ishin no Kai Maehara was elected as co-leader of Ishin after the
2024 general election. While
Osaka Governor
Hirofumi Yoshimura was elected party leader, Maehara was made the party's parliamentary representative in the
National Diet. He spoke at the
Center for Strategic and International Studies in May 2025. After the
2025 House of Councilors election, in which Ishin lost 2 seats in the Upper House, Maehara and three other party executives announced their intention to resign. After Maehara resigned as co-leader, former party Secretary-General
Fujita Fumitake was elected to replace him on 8 August 2025. Maehara was elected chairman of the House Committee on National Security in October 2025. == Political positions ==