But a low turnout from unenthusiastic voters beset by a heavy snowfall could cast doubt on the endorsement he will claim for “Abenomics” — his signature plan to fix the country’s flaccid economy.
Broadcasters’ exit polls shortly after voting finished showed his ruling Liberal Democratic Party (LDP) and its junior partner Komeito had swept the ballot, with an unassailable two-thirds majority that will give them the power to override the upper house.
TV Asahi said the pairing had won 333 of the 475 seats, while TBS put the figure at 328.
“I have been pushing for Abenomics, the policies designed to create jobs and raise salaries,” Abe told hundreds of voters in Tokyo’s neon-lit Akihabara electronics district on the eve of the election.
“Japan can be much richer,” Abe said, sporting a knee-length white windbreaker emblazoned with his campaign slogan: “This is the only way”.
Abe, 60, was only halfway through his four-year term when he called the vote last month.
The first two of his “three arrows” of Abenomics — monetary easing and fiscal stimulus — have largely hit their targets; the once-painfully high yen has plunged and stocks have risen dramatically.
Prices have also begun rising after years of treading water — proof, says Abe, that this is the beginning of a virtuous circle of economic growth, with higher wages soon to follow.
However a sales tax rise in April snuffed out consumer spending, sending Japan into the two negative quarters of growth that make a recession.
Economists say more important than the sugar rush offered by easy money and government spending is structural reform of Japan’s highly-regulated and protected economy — the third arrow of Abenomics.
Abe has been criticised for not being bold enough in taking on the vested interests that are the real key to reversing nearly two decades of economic underperformance.
His fresh four-year mandate may stiffen his resolve for these reforms and see off opposition from within his ill-disciplined LDP, a party given to bouts of regicide.
But with only 34.98 percent of voters casting ballots by 6pm (0900 GMT), there may be questions over whether this really is an endorsement, or just the default reaction of an electorate numbed by a lack of viable alternatives.
The turnout at that point was down 6.79 points from the 2012 election. But early voting — which was completed by Saturday — was up by almost a tenth from the previous poll, to around 13 million ballots, according to the government.