By Linda Sieg and Yoko Kubota
TOKYO (Reuters) - Unpopular Japanese Prime Minister Taro Aso's job could be at risk after projections showed the opposition Democratic Party winning the most seats in a Tokyo poll on Sunday seen as a barometer for a national election.
NHK public TV and Kyodo news agency said Aso's ruling bloc was also in danger of losing its majority in the Tokyo assembly, a defeat expected to intensify moves by his Liberal Democratic Party (LDP) to ditch the prime minister ahead of a general election due by October.
Aso has been thought to be eying an early August national vote, but many in the LDP were already opposed to a move they fear would be political suicide.
NHK public TV said Chief Cabinet Secretary Takeo Kawamura and LDP Secretary General Hiroyuki Hosoda agreed in talks on Sunday that the outcome of the Tokyo vote would not affect national politics and that Aso would not be blamed for a defeat.
However, Kyodo quoted another unidentified ruling party executive as saying: "This is a great blow against the Aso government."
The long-ruling LDP has been wracked by internal dissension of late, with Aso critics openly urging an early party leadership vote to replace him while his allies defend his right to call a general election at a time of his own choosing.
Close Aso ally Yoshihide Suga, deputy chairman of the LDP's election strategy council, denied earlier on Sunday that the party might bring forward a leadership vote and replace Aso ahead of the national election.
"That is impossible," he said in a debate on Fuji TV. "Of course it will be the prime minister who calls the election."
NEARLY UNBROKEN RULE
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 his 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 Jon Boyle)