The victory may be propelled by what is seen as a wave of sympathy votes in a country still reeling from the shock of the former prime minister's assassination.
Tetsuya Yamagami, the unemployed 41-year-old who confessed to assassinating Shinzo Abe, reportedly planned the attack for months. He told police his motivations were not political.
The influential prime minister worked to revive the economy with his trademark "Abenomics" and rebuild Japan's role on the global stage. His assassination stunned a nation where gun violence is rare.
Japan, with famously strict laws, has among the world's lowest rates of gun ownership and gun violence. In 2018 there were just nine firearm deaths reported in Japan, compared with 39,740 in the U.S.
Japan's former Prime Minister Shinzo Abe was in heart failure after apparently being shot during a campaign speech Friday in western Japan, NHK public television said.
Weather officials announce the earliest end to the country's annual summer rainy season since the Japan Meteorological Agency began keeping records in 1951.
The Osaka court ruling underscores how divisive the issue remains in Japan, the only member of the Group of Seven major industrialized nations that does not recognize same-sex unions.