Japanese Prime Minister Shinzo Abe’s ruling coalition was on course for a major victory in national elections, exit polls showed on Sunday.
His Liberal Democratic Party-led (LDP) coalition was set to win 311 seats, keeping its two-thirds "super majority" in the 465-member lower house, an exit poll by TBS television showed.
The victory would boost his chances of winning another three-year term next September. That could extend his premiership to 2021, giving him more time to pursue his goal of revising Japan's post-war constitution.
It also means his "Abenomics" growth strategy centered on the hyper-easy monetary policy will likely continue.
Final official results are expected early on Monday.
Abe dissolved the lower house less than a month ago, forcing the snap election. Up for grabs are 465 seats in the more powerful chamber, which chooses the prime minister.
Analysts initially thought that a new opposition party launched by populist Tokyo Governor Yuriko Koike could put a dent in the ruling coalition's majority.
But Japanese public broadcaster NHK projected that Koike's Party of Hope would win just 38 to 59 seats in the 465-seat lower house.
Koike called the results "very severe" in a televised interview from Paris, where she is attending a conference of mayors. She said some of her remarks might have been taken negatively by voters, and that she would take the blame.
Revising Japan's post-war pacifist constitution has been Abe’s longtime goal.
The US-drafted constitution's Article 9, if taken literally, bans the maintenance of armed forces. But Japanese governments have interpreted it to allow a military exclusively for self-defense.
Backers of Abe's proposal say it would just codify the status quo. Critics fear it would allow an expanded role overseas for the military.
The Komeito is cautious about changing the constitution, drawn up after Japan's loss in World War Two. Several opposition parties favor changes, but do not agree on details. Amendments must be approved by two-thirds of each chamber of parliament and then by a majority in a public referendum.
"Nothing about the process (of revising the constitution) will be easy," said Tobias Harris, an analyst at Washington-based consultancy Teneo Intelligence. "But we'll be hearing a lot about it."
Abe had said he needed a new mandate to tackle a "national crisis" from North Korea's missile and nuclear threats and a fast-aging population, and to approve his idea of diverting revenue from a planned sales tax hike to education and child care from public debt repayment. He called the poll amid confusion in the opposition camp and an uptick in his ratings, dented earlier in the year by suspected cronyism scandals.
Abe's move had seemed risky after Koike, often floated as a possible first Japanese female premier, launched her conservative Party of Hope.
The Party of Hope absorbed a big chunk of the failed main opposition Democratic Party. But voter enthusiasm soon waned despite its calls for popular policies such as an exit from nuclear power and a freeze on the planned sales tax rise.
Koike did not run for a lower house seat herself - she was in Paris for a climate change event on Sunday - and failed to say whom her party would back for prime minister.
A new Constitutional Democratic Party of Japan (CDPJ), formed by liberal former DP members, was vying with Koike's party for the top opposition spot - the TBS exit polls had the CDPJ beating out the Party of Hope - although both will have just a sliver of the LDP's presence if forecasts prove accurate.
"Day by day, we felt we were getting more voter support for our call to revive more decent politics, and not fret about whether it's right or left wing - and instead to push things forward," Tetsuro Fukuyama, a CDPJ member in parliament's upper house, said on NHK.