- Shinzo Abe's Liberal Democratic Party wins upper house parliamentary vote
- LDP and partner Komeito took at least 74 of 121 seats contested
- Sunday's result will be read as an endorsement of Abe's expansionary economic policies
- Dubbed "Abenomics," government spending has risen, monetary policy loosened
Shinzo Abe, Japan's prime minister, pledged to keep his focus on the economy and suggested he would defer his ambition to rewrite the country's constitution after his Liberal Democratic party won a sweeping victory in elections for the upper house of parliament on Sunday.
The LDP and its smaller partner, Komeito, took at least 74 of the 121 seats contested, according to a still-partial vote count late on Sunday night. The victory, which had been widely predicted, will put the coalition in charge of both houses of parliament for the first time since 2007.
"A majority of the people have shown their desire for a steady political situation in which decisions can be made and there can be forward progress on economic policy," Mr Abe said.
With advance surveys having left little doubt about an LDP victory, much of the attention has been focused on Mr Abe's post-election agenda.
He has made the economy a priority since the LDP took power in elections for parliament's more powerful lower house in December, but has been clear about his desire to revise the anti-war constitution -- a large project that would be bound to consume much of the government's energy and strain its public support.
"We still need a deep and wide national discussion [about the constitution] and I want to proceed unhurriedly, in a situation of stability," Mr Abe said. "We still have homework to do."
Changing the constitution would require the assent of two-thirds of members of both houses of parliament, plus a majority of voters in a national referendum -- high hurdles that LDP strategists say the party is not yet ready to clear. Even with its big victory on Sunday it is still short of the required super-majority in the upper house, where only half the seats are contested at a time.
Sunday's result will be read as an endorsement of Mr Abe's expansionary economic policies, dubbed "Abenomics", which have lifted the stock market and aided export-dependent manufacturers by reversing a six-year appreciation of the yen. In exit polls, 72 per cent of respondents told NHK they approved of the premier's handling of the economy.
Abenomics' most tangible features so far have been increased government spending and a dramatic loosening of monetary policy by the Bank of Japan.
Mr Abe has also sketched out a "national growth strategy" that includes wide-ranging structural reforms and deregulation, but details of many of his initiatives have been scarce so far. A more concrete set of proposals has been promised for September.
Many will require new legislation, which Mr Abe will be able to pass more easily with the entire parliament under LDP control. Keeping his own often reform-averse party united behind his agenda may be the more difficult task.
The election could usher in a period of stability in a country that had cycled through six prime ministers in six years. Barring an early dissolution of parliament, the LDP will not face another national election until 2016.
The LDP had secured 64 seats by late Sunday night, matching the record number it won in 2001 under Junichiro Koizumi, Japan's last long-serving prime minister. Nine seats were still up for grabs, meaning it was likely ultimately to surpass that number.
Komeito added at least 10 seats to the coalition's total.
The struggling Democratic Party of Japan (DPJ), which the LDP defeated in December, had 15 confirmed seats and was set for its lowest total under the present election system.
In the Tokyo suburb of Chiba, Sadao Sato, 48, an employee of an automobile sales company, said he hoped a strengthened LDP government would improve the economy. "But at the same time," he said, "I am concerned about this huge victory because they may do whatever they want to do in a selfish way."