The Liberal Democratic Party candidate was assured of victory by a slim margin in a by-election Sunday in Saitama Prefecture, dealing a blow to the major opposition Democratic Party of Japan before the Nov. 9 general election.
The LDP's Masakazu Sekiguchi, a 50-year-old former member of the prefectural assembly, edged out the DPJ candidate Chiyako Shimada, a 41-year-old former TV anchorwoman.
With 94 percent of the ballots counted, Sekiguchi garnered 607,689 votes against 603,955 for Shimada. Sachiyo Abe, 55, of the Japanese Communist Party was in third with 216,846.
The election for a House of Councilors seat was the first since Koizumi reshuffled his Cabinet last month. It has been viewed as a litmus test for the Nov. 9 general election for the House of Representatives.
Voters in Saitama are less conservative than in many other prefectures. Former DPJ lawmaker Kiyoshi Ueda was elected governor there in August.
Voter turnout was a meager 27.52 percent, down 25.09 percentage points from the previous Upper House election.