Yasuo Fukuda, Japan’s former chief cabinet secretary is likely to be elected chairman of his Liberal Democratic Party (LDP) and succeed outgoing Prime Minister Shinzo Abe, media reports said Thursday.

Most LDP members threw their support behind the 71-year-old politician and turned him into a frontrunner in the race for the party’s leadership. The campaign will end by Sunday, when the party which led Japan continuously for more than five decades will elect a new leader.

The LDP chairman will automatically become the country’s prime minister since the LDP has an absolute majority in the lower house. The next premier will be officially chosen Tuesday, when all ministers from Abe’s cabinet are expected to step down, as Chief Cabinet Secretary Kaoru Yosano said.

According to the latest opinion polls, nearly 70 per cent of the lawmakers will vote in favour of Fukuda, 387 LDP members and 141 from local chapters being expected to vote on Sunday.

The polls revealed that nearly 60 LDP lawmakers haven’t decided which one of the candidates gets their vote. Reports said Fukuda will battle with LDP General Secretary and former foreign minister Taro Aso for the party’s leadership.

A runoff election will be held Tuesday in upper house, with opposition members supporting Democratic Party of Japan (DPJ) President Ichiro Ozawa in the election.

The DJP won majority in the House of Councillors in July, but even so it can’t override the majority held by the LDP in the House of Representatives, and Japan’s new prime minister will be the ruling party’s chairman.

Shinzo Abe decided to submit his resignation last week after almost a year in office and was hospitalized the next day, doctors saying exhaustion and stress caused his illness, a gastrointestinal disorder.

Abe was the target of heavy criticism from numerous politicians, who said he wasn’t able to tilt up the government’s plummeting popularity and left office without apologizing for the crisis that emerged during his term at the helm of Japan.

Meanwhile, Fukuda received much of the support after he revealed his policy and said Japan must focus on tighter diplomatic relations with other Asian nations.