Prime Minister Shinzo Abe's chances for becoming the nation's longest-serving leader in more than four decades are increasing as the opposition finds itself hobbled by factionalism, shifting policies and funding shortages.

The Dec. 14 victory in the Lower House election that the public opinion polls are predicting would strengthen Abe's grip over his Liberal Democratic Party ahead of a leadership vote next September. A new three-year term as party chief, plus a win in the 2016 Upper House election, would see his command stretch to 2018.

While Abe's policies have damaged household spending power by eroding real income, and have featured unpopular moves to restart nuclear reactors and loosen limits on the Self-Defense Forces, the opposition has failed to make inroads with voters.