In an apparent bid to refresh the image of the Democratic Party, some members of the main opposition force Thursday expressed hope that Yuichiro Tamaki, who is seen as a young hopeful lawmaker, will run in the party leadership race in September.

Tamaki, 47, is in his third term as a Lower House lawmaker and is a former finance ministry bureaucrat who often grills Prime Minister Shinzo Abe and his Liberal Democratic Party-led Cabinet in Diet sessions.

The DP has been struggling with a negative image since its predecessor group, the Democratic Party of Japan, fell from power after being in control of the government between 2009 and 2012. It has suffered at the hands of the ruling LDP in recent elections, including the July Upper House poll and Sunday's Tokyo gubernatorial race.

Thus there have been strong voices within the DP, which was formed in March via a merger of the DPJ and Ishin no To (Japan Innovation Party), urging a generational turnover to create a fresh image for the party.

For the September race, several other names have been floated in the past few days.

Renho, a deputy party leader, is expected to announce her candidacy on Friday.

Former Foreign Minister Seiji Maehara and former Senior Vice Defense Minister Akihisa Nagashima are also looking to join the race, while it is unclear whether they can collect the endorsements of at least 20 lawmakers within the party, which is necessary to be a candidate.

Current party leader Katsuya Okada already announced he will not seek re-election.