Japanese Prime Minister Yoshihiko Noda speaks during a press conference in Tokyo after winning the Democratic Party of Japan’s leadership election on Sept. 21. (Shizuo Kambayashi/AP)

Japanese Prime Minister Yoshihiko Noda easily defeated three challengers in a ruling party election Friday, earning him the right to keep his job at least a while longer as Japan deals with a controversial new energy policy and a territorial spat with China.

In the vote by party lawmakers and regional members, Noda garnered 68 percent of the tally. But that overwhelming victory, political analysts said, shows only that he is well supported by a ruling party that the country seems poised to oust.

Noda’s Democratic Party of Japan has an approval rating in the teens, according to some polls here, and his rating hovers near 30 percent. Barring an unlikely turnaround, the DPJ will lose power in the next parliamentary elections, expected in the coming months. That means a new party, probably the Liberal Democratic Party, will take control and its party president will replace Noda as Japan’s leader.

During his one-year tenure, Noda has proved himself more capable than the five leaders who briefly held the office before him, securing rare cooperation from opposition parties to pass a consumption tax increase that will help fund social security costs.

But Noda has lost support along the way. During the fierce debate over the tax increase, a handful of DPJ members defected. Noda, more recently, has also had to contend with a territorial dispute with China in which he faces domestic pressure to get tough, potentially enraging Beijing, and maintain calm, given the neighbors’ deep trade ties.

Separately, Noda invited criticism earlier this week when his cabinet did not endorse a government plan to eliminate nuclear power by the 2030s; ministers watered down the plan’s language and said the government must engage in “ongoing studies” about the best approach.

A survey published in July by the Pew Research Center showed that 78 percent of Japanese are dissatisfied with the country’s direction.

Noda faces pressure from opposition parties to dissolve the powerful upper house and call a snap election, but analysts say the prime minister is trying to put off any vote, hoping his party can regain popularity.

Legally, Noda is not obligated to call an election until next August. But Japan will not be able to pass upcoming legislation — including a bill to allow the issue of deficit-covering bonds — without cooperation from the opposition, something that might depend on a promise to hold a vote.