Japanese voters went to the polls Sunday in an election expected to strengthen Prime Minister Shinzo Abe's hand, potentially giving him power to push much-needed economic reforms.
Half of the 242 seats in the upper legislative chamber are up for grabs, in what is expected to be the last national election for three years.
Voting began at 7:00 am (2200 GMT Saturday) across the nation. Booths close at 8:00 pm with broadcasters' exit polls expected shortly thereafter.
Voter turnout stood at 13.73 percent as of 11:00 am (0200 GMT), down 2.86 percentage points from the previous upper house poll in 2010.
With approval ratings well over 60 percent on average since December when he won the premiership in a general election, a win for the hawkish premier's ruling bloc is all but assured.
Control of both chambers will remove political obstacles to Abe's agenda.
"This election is a fight to achieve political stability," Abe's Liberal Democratic Party said in a statement released ahead of the voting. "By winning the fight, our party can assume our responsibility to the nation."
Supporters say that will give him free rein to force unpopular changes on Japan's long under-performing economy.
They point to the need for reform of the labour market to make it easier for firms to hire and fire workers, participation in a huge free trade pact and a rise in consumption tax, which economists say will help to slow the pace of growth in the already sky-high national debt.
The reforms are the third instalment of an economic policy plan dubbed "Abenomics" that has already seen a slew of government spending and a flood of easy money from the central bank.
Those moves pushed the value of the yen down and sent the stock market soaring, bringing cheer to some sectors of corporate Japan.
"We are at the threshold of economic recovery," Abe told voters on the eve of Sunday's voting. "There is no mistake about the policies that we are currently carrying out."
However, Abe's detractors say Abenomics is a ruse, part of a tactical power grab that will see the premier return to his conservative social agenda once he has control over both houses of parliament.
They fear this will mean a loosening of Japan's constitutional commitment to pacifism, a boosting of the military and a more strident tone in already-strained relations with China and South Korea, both of which have territorial disputes with Tokyo.
Whatever Abe's intentions, the predicted swing towards his LDP and its junior coalition allies could give Japan its first long-term prime minister since Junichiro Koizumi, who ruled for the first half of last decade.
"The Abe administration can become a long-run regime," said Koji Nakakita, professor of politics at Hitotsubashi University in Tokyo. "It even has the potential to go beyond the next three years."
Many voters voiced hope for economic recovery under Abe's leadership, while others cried over the weakened opposition.
"I expect the Abe cabinet will exercise his strong leadership to push for recovery so that we can actually share and feel it," Masako Suzuki, a 82-year-old pensioner said at a Tokyo polling station.
Miho Sugiyama, a 35-year-old Internet firm executive, said: "I can't vote for any opposition parties, which are all lacking ability to take action. I don't expect much from the current opposition."
The largest opposition Democratic Party of Japan, which lost power to Abe's LDP in last year's lower house election, is expected to suffer another blow in Sunday's poll, according to surveys.