Unpopular Japan PM's job on line in Tokyo vote

TOKYO (Reuters) - Unpopular Japanese Prime Minister Taro Aso's job will likely be on the line if, as many expect, his ruling party fares badly in a key local election on Sunday that is seen as a bellwether for a looming national poll.

The main opposition Democratic Party has outstripped Aso's long-ruling Liberal Democratic Party (LDP) in opinion polls ahead of the closely watched election for the Tokyo Metropolitan Assembly, mirroring its lead for the upcoming national election.

Ruling party moves to oust Aso, whose support among voters has sunk below 20 percent in some surveys, are set to intensify if the Democrats and other opposition parties outperform the LDP and its partner, the New Komeito, in the Tokyo assembly vote.

An election for parliament's lower house must be held by October and Aso is thought to be eying an early August vote, but many in the LDP oppose a move they fear would be political suicide.

Close Aso ally Yoshihide Suga, deputy chairman of the LDP's election strategy council, denied on Sunday that the party might bring forward a leadership vote and replace Aso ahead of the election.

"That is impossible," he said in a debate on Fuji TV. "Of course it will be the prime minister who calls the election."

POSSIBLE SUCCESSORS

A Democratic Party victory in the lower house election would end half a century of nearly unbroken rule by the business-friendly LDP and raise the chances of resolving a deadlock in a divided parliament as Japan tries to recover from its worst recession since World War Two.

Aso's term as LDP leader expires in September and critics in the party are keen to bring forward the leadership vote to replace him ahead of the general election.

Possible candidates to replace Aso include Minister of Health, Labour and Welfare Yoichi Masuzoe, 60, a former academic and TV commentator seen as competent and hardworking.

But Aso is Japan's third premier to take office since Junichiro Koizumi led the party to a huge win in a 2005 election, so voters might not be impressed with another change at the top.

The Democrats, hoping to intensify pressure on the ruling bloc, are considering submitting a no-confidence motion against Aso in the lower house.

But Japan's biggest opposition party has its own headache.

Democratic Party leader Yukio Hatoyama has apologised for the fact that some people listed as his political donors were dead. But the LDP -- although far from immune to scandals itself -- is pressing for him to appear in parliament over the affair.

Hatoyama took over as party leader in May after his predecessor stepped down to keep a separate fundraising scandal from hurting the party's chances at the polls.

(Editing by Jeremy Laurence)