Japanese Prime Minister Naoto Kan urged voters to give his party a second chance in a weekend election that could deliver a sharp setback to his government, putting his job at risk and stalling efforts at fiscal reform. Sagging support for the Democratic Party of Japan (DPJ), which surged to power for the first time just last year, jumped after Kan - a former civic activist and Japan's fifth leader in three years - replaced his indecisive predecessor last month. But ratings slipped after Kan floated the long taboo topic of raising the sales tax to curb a public debt close to twice the size of the nearly £3.3tn economy, and struggled to persuade voters he had a clear plan for fixing Japan's economic woes. Since then, Kan has stressed that no tax hike would occur before seeking a mandate in the next lower house poll, which must be held by late 2013, but argued that Japan could not put off painful choices if it wants to avoid a Greek-style debt crisis. "Japan's economy is 20 to 30 times bigger than that of Greece and its public debt is huge, so no country in the world could rescue Japan," Kan told a crowd of voters sweltering on Saturday under the hot sun in a popular shopping area of western Tokyo. "Japan itself must make sure it avoids collapse," he said, adding ordinary folk would suffer most if finances crumbled. The DPJ, which ousted its long-dominant rival last year with pledges to cut waste, end bureaucrats' control over policymaking and spend more on consumers to boost growth, will almost certainly run the government whatever the outcome of Sunday's vote because it controls the powerful lower house. Media surveys this week showed the DPJ would likely win around 50 or even fewer of the 121 seats up for grabs in the 242-member chamber - well short of Kan's target of keeping all 54 seats the Democrats have up for re-election.