Following a close runoff against the younger Goshi Hosono after a weeklong campaign, Katsuya Okada was elected president of the Democratic Party of Japan on Sunday.

Okada, 61, headed the party between 2004 and 2005 and served as secretary-general several times. But questions remain over whether the veteran can pull the largest opposition force together and regain the public’s trust.

Okada, backed by the DPJ’s “mainstream” members, defeated Hosono 133 to 120 in the runoff, which was based on the votes of Diet members and one candidate running for the next Upper House election. The runoff was held immediately after it was determined none of the three had garnered 50 percent or more of the votes in the first poll.

Former health minister Akira Nagatsuma, 54, who was backed by the party’s liberal members, was trounced in the first round.

Okada will replace Banri Kaieda, who lost his Lower House seat in December’s snap general election.

“We will gain a majority in the next general election. . . . It’s also important to win the next Upper House election. We will aim for winning a majority,” Okada said at a news conference after the runoff.

Okada said he has not decided how to fill the party’s executive posts yet.

With the election over, focus shifts to ways to rebuild a party that has struggled to turn itself around since its devastating defeat in the December 2012 election.

But how Okada can clearly differentiate the party from the ruling LDP is still unclear because he does not completely oppose Prime Minister Shinzo Abe on such issues as nuclear power plant restarts and his “Abenomics” strategy. As for exercising collective self-defense, Okada pledged to fully discuss the matter in the Diet to see if its use can be limited.

“I want to take the lead in the Diet deliberation. Solid discussion is necessary (at the Diet) centering around the economy, the statement by the prime minister to mark the 70th anniversary of the end of the war, and security legislation,” Okada said.

As the next Upper House election is scheduled for 2016, Okada is preparing to select candidates. Stressing the importance of increasing the number of female lawmakers, Okada has said he will publicly seek female candidates soon.

Although Okada has repeatedly denied any possibility of the DPJ merging with Ishin no To (Japan Innovation Party), the second-largest opposition party, he reiterated the importance of cooperating with the other opposition parties in the Diet and in elections.

Kazuhisa Kawakami, a political science professor at Meiji Gakuin University, said even with the change at the helm, the DPJ has a grim chance of gaining wider public support.

“I don’t expect the party’s support rate to go up even with the change of the party’s leader,” Kawakami told The Japan Times.

If the DPJ really wants to rebuild itself in ways strong enough to face off with the LDP, the party needs to gain support from voters other than labor unions, he said.

Throughout the recent presidential election campaign, he didn’t see such sense of crisis among the candidates, Kawakami said.

A merger with Ishin is one possible way to expand voter support, Kawakami said, but added that Okada is unlikely to follow such a path.

“So the chance for the DPJ to boot itself up is when the ruling camp makes crucial mistakes that trigger anger from citizens, such as (any) failure of Abe’s economic policies,” Kawakami said.

“But sadly, even if such a thing happens, as I see the current state of the party, I don’t think it will raise hopes for the DPJ among swing voters,” he said.

Okada is to serve as party head until September 2017.

It was the first DPJ presidential election in which the votes of its rank-and-file members and supporters outweighed those of its Diet members.

In his own words, party members view Okada as a fundamentalist, but he said he is comfortable with that view.

“I’m nicknamed as ‘fundamentalist.’ I believe this is a word of praise,” Okada in a speech before the final vote Sunday.

“It’s quite important for a politician to stand firm and not to waver. But that doesn’t seem to be all the things” the nickname means, he said, drawing laughter from the audience.

Okada is known as a sharp debater with extensive knowledge of policy matters. He was popular during his last stint as party leader in 2004 and 2005.

But at the same time, he has often been criticized for lacking flexibility and being too strict with others, failing to win the hearts of many Diet members.

Thus Okada, who is often satirically called a “policy fundamentalist,” does not have a large number of close followers in the Diet. The last time he ran in a DPJ presidential race, in 2009, he lost to Yukio Hatoyama, who became its first prime minister later that year.

“Some friends say I don’t listen to what people are saying to the end. Others say I’m not very warm-hearted,” he said.

“I myself need to change,” Okada said in his final appeal to the Diet members right before the second round of voting.

At Sunday’s party convention, DPJ members elected Okada after apparently preferring his experience and stability as party leader to the freshness of rival Hosono, who would have promoted a generational change of party executives if elected.

But as Okada pointed out, whether the party and Okada himself can drastically change their public images is the most important question the party faces. Polls have shown voters were deeply disappointed with the way the party operates.

Okada, a Lower House member elected from the No. 3 district of Mie Prefecture, is a son of Takuya Okada, founder of the Aeon supermarket group, one of the largest retailing businesses in Japan.

After graduating from the law faculty at the University of Tokyo, he joined the powerful Ministry of International Trade and Industry in 1976. After leaving in 1988, he was elected to the Lower House for the first time as a member of the Liberal Democratic Party in 1990.

He jointed the DPJ in 1998. Since then, Okada has been one of its key DPJ executives.

He served as foreign minister under Prime Ministers Yukio Hatoyama and Naoto Kan in 2009 and 2010, respectively, and then was deputy prime minister in charge of social security and administrative reforms in 2012 in the Cabinet of Prime Minister Yoshihiko Noda.

As a deputy chief of the DPJ, Okada was among top party executives who organized election campaigns during the latest Lower House election in December.