Doi Resigns as Leader of Japan Socialists : Politics: She was the first woman to head a major party and once was seen as a serious contender for prime minister.

TOKYO —  Takako Doi, the first woman to lead a major Japanese political party, resigned Friday as head of the Socialists after a frustrating string of political defeats.

As chairwoman of Japan’s largest opposition party, the charismatic Doi led the Socialists to unprecedented election victories two years ago and was even seen by some as a serious contender for prime minister.

But with the conservative Liberal Democratic Party still solidly in power and with the Socialists once again embroiled in battles over doctrine and strategy, Doi tendered her resignation.

She stepped down after meetings Friday with party executives, including Vice Chairman Makoto Tanabe, a man who is expected to assume her post after a formal party election next month.

“There is no one in postwar politics who has brought politics so successfully into people’s living rooms,” Tanabe recently said in an interview with one of Japan’s leading newspapers.

Doi, 62, became the Socialists’ chairwoman in 1986, as the fractious party struggled to recover from an election drubbing at the hands of the governing party.

She was lifted to national prominence after elections in the summer of 1989, when her party nearly doubled its strength in the upper house of Parliament. It marked the first time the Liberal Democrats lost control of that body.

Along with Doi’s charm, the Socialist victory was the result of voters’ anger over the introduction of a sales tax championed by the Liberal Democrats and an influence-peddling scandal that tainted most of its leaders.

But the Socialists, who recently renamed their party the Social Democratic Party, failed to unite behind a coherent platform. Since then they have slipped back out of the political mainstream.

Drubbings in local elections in April resulted in calls for Doi’s resignation. She was also criticized for challenging Prime Minister Toshiki Kaifu’s Persian Gulf War policies without offering an alternative.

The government pledged nearly $11 billion in assistance for the allies that drove Iraq out of Kuwait and sent minesweepers to help clear the gulf of mines after the war ended.