Shinjirō Koizumi

Japan's Prime Minister Shigeru Ishiba vowed Monday to stay in office despite his gamble of snap elections backfiring, with the ruling party's worst result in 15 years.

Ishiba, 67, called Sunday's election days after taking office on Oct. 1, but voters angry at a slush fund scandal punished his Liberal Democratic Party (LDP), which has governed Japan almost non-stop since 1955.

New Japanese Prime Minister Shigeru Ishiba's snap election gamble could backfire this weekend, with his ruling party at risk of losing its majority for the first time in 15 years.

Ishiba took office and called an election less than a month ago after a tough contest within the Liberal Democratic Party (LDP), which has governed for all but four of the last 69 years.

Japan's new prime minister will be formally elected by parliament on Oct. 1 following next week's leadership contest, a ruling party official said on Wednesday.

Polls indicate that three frontrunners are emerging among the nine candidates to succeed Fumio Kishida as head of the Liberal Democratic Party (LDP) in the Sept. 27 internal vote.

Japan's leadership race kicked off on Thursday with a record nine candidates, including the surfing son of a former prime minister and an arch-nationalist, vying to be the first woman premier.