TOKYO, Oct 18 (Reuters) - Japanese Prime Minister Fumio Kishida is seeking to steal opposition thunder at this month"s general election by mimicking their criticism of predecessor Shinzo Abe"s "Abenomics", promising to shrink income gaps and bolster the middle class. Kishida, who served as foreign minister under Abe, could help his Liberal Democratic Party (LDP) limit losses in the Oct. 31 poll by blurring differences to the opposition by calling for a "new capitalism" that would spread the benefits of growth. The LDP faces an opposition more united than at any time in nearly a decade and is expected to lose seats after a huge win in 2017. Although the ruling bloc is likely to keep its lower house majority and hence, its grip on power, big losses would make it more likely Kishida ends up another short-term premier. Borrowing from the opposition"s policy playbook is a tactic the long-ruling LDP has often used with success. "If voters can"t understand the difference, it favours the party in power," said Steven Reed, professor emeritus at Chuo University. The mild-mannered Kishida won a four-way party leadership race last month after then premier Yoshihide Suga bowed out after just one year in office, his ratings in tatters over his handling of the COVID-19 pandemic. Kishida - whose victory in the party race ultimately relied on Abe"s help and whose cabinet includes Abe acolytes - has not abandoned central tenets of Abenomics: massive monetary and fiscal stimulus. "Kishida acknowledges that Abenomics ended deflation, so rather than criticising it, he"s saying disparities grew and distribution of wealth to those who didn"t benefit is needed," said an LDP lawmaker, speaking on condition of anonymity. Still, Kishida"s campaign acknowledges that nearly nine years of "Abenomics" stimulus under Abe and Suga failed to cure gaps that widened as the ranks of workers in less-secure, low-paid jobs grew. In its platform, the LDP pledged to "rebuild a robust middle class with a "new capitalism". That echoes the main opposition Constitutional Democratic Party of Japan"s (CDPJ) call to "restore a society with a 100-million strong middle class". ABENOMICS NOT ABANDONED Last week, Kishida launched a flagship panel to look into wealth distribution, arguing market competition alone would not "deliver the fruits of growth to the broader population". The LDP platform, however, dropped Kishida"s call for an income doubling plan and a capital gains tax hike that had spooked the stock market - a major beneficiary of Abenomics - leaving him vulnerable to criticism for flipflopping. The pro-business LDP, in power for most of the decades since its formation in 1955, has long accommodated a wide-range of policies from big government to pro-market reform. And to be sure, Kishida"s mantra differs from that of the CDPJ. The opposition party says redistribution is a prerequisite for growth, while Kishida insists growth takes priority - a stance that in fact, is similar to Abe"s long-held position. "He needed to sound sort of new, and to sound new, he needed to sound critical, but he can"t overdo the critical part," said Sophia University political science professor Koichi Nakano. Both ruling and opposition parties have come under fire for a lack of funding details in the face of Japan"s huge public debt, prompting a rare open rebuke from the top finance ministry bureaucrat for engaging in a "pork barrel battle". Kishida"s initial ratings, while higher than Suga"s just before he bowed out, were lower than for most new premiers - a worry for his party. But if confused voters stay home, low turnout would benefit the LDP, which can count on organised groups to send members to the polls. "The LDP platform doesn"t need to be credible - just enough that people will not vote for the opposition, or not vote at all," Nakano said.