Japan PM picks up support as party wins local poll

Japan's Prime Minister Naoto Kan waves to voters on the last day of a stumping tour before Sunday's upper house election in Kawasaki, south of Tokyo, July 10, 2010.

TOKYO (Reuters) - Support for Japanese Prime Minister Naoto Kan's government picked up slightly, surveys showed on Monday, as a local election victory gave temporary relief to the struggling premier ahead of a party leadership vote next month.

Kan, under pressure to deal with risks of policy gridlock in Japan's hung parliament, is fighting for his political life as he faces a potential challenge in the Sept. 14 election for the head of the Democratic Party.

Voter support for Kan's government, which has been slipping from over 60 percent since he took office in June, rose to 38.7 percent, a survey by Kyodo news agency showed. It was up 2.4 points from last month's survey. In another poll by national broadcaster NHK, the support rate also edged up to 41 percent, up 2 points from a survey in July.

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In the first electoral test for the Democrats since their coalition lost its upper house majority in July, Shuichi Abe, who had worked in a government unit focusing on cutting waste, won Sunday's gubernatorial election in Nagano prefecture, northwest of Tokyo.

"This is big for the Democratic party. It will be the first step toward rebuilding," said Jun Azumi, chairman of the party's election campaign committee.

The Democrats, desperate to avoid another election setback, had sent popular cabinet ministers to Nagano to support Abe, whose principal rival was backed by the main opposition Liberal Democratic Party.

KAIEDA AS POTENTIAL RIVAL

While the local election victory could mean a respite for Kan, his Democratic Party faces political deadlock unless it can find new allies to help enact bills as the government struggles to curb Japan's mountain of public debt, nearly twice the size of its $5 trillion economy, and engineer sustainable growth.

Analysts also worry about a possible political vacuum until the party leadership vote.

Kan may face a challenge from party powerbroker Ichiro Ozawa or a proxy candidate in the vote for party chief next month. Ozawa was sidelined during the upper house election in an effort to woo voters put off by his scandal-tainted image.

Kan is so far the only declared candidate for party chief, but Banri Kaieda, chair of the lower house's financial services committee and a former party policy chief, has told the Ozawa camp of his willingness to run, weekend media reports said.

The Democratic Party will remain in power by virtue of its grip on parliament's more powerful lower house and the winner of the ruling party leadership vote would effectively be chosen as Japan's prime minister.

Despite sluggish voter support, public opinion polls show most respondents see no need for Kan -- Japan's fifth premier in three years -- to quit, a sign of rising irritation with revolving-door prime ministers.

Kyodo's survey showed the favourite candidate among respondents was Kan, with 37.2 percent of them saying they want Kan to win the party leadership election.

(Editing by Edmund Klamann and Sanjeev Miglani)