Party leaders sought voter support nationwide on Saturday, wrapping up more than two weeks of official campaigning for the Upper House election.
Prime Minister Shinzo Abe, who heads the ruling Liberal Democratic Party, has pushed constitutional revision as one of the main issues for Sunday's election in which 370 candidates will vie for 124 seats.
But the reliability of the public pension system has also come under intense scrutiny after an alarming report issued by the Financial Services Agency earlier this month estimated that a retired couple would face a shortfall of ¥20 million under the system's current parameters if they live to be 95 years old.