TOKYO, March 8 (Reuters) - Almost 60 percent of Japanese voters want opposition leader Ichiro Ozawa to resign after the arrest of a senior aide clouded his party's prospects in a looming election, a newspaper poll said on Sunday.
The Mainichi Shimbun poll also showed that 79 percent of respondents felt Ozawa's explanation of the fund-raising scandal in which his aide was arrested was not sufficient, while 12 percent said it was acceptable. The rest did not answer.
The daily polled 1,032 respondents on Friday and Saturday.
Ozawa's aide was arrested last week on suspicion of taking illegal corporate donations. The scandal involved mid-sized contracting firm Nishimatsu Construction Co Ltd.
Democratic Party leader Ozawa said he would not resign but the scandal has damaged his party's chances in the election, which must be held by October.
Ozawa's Democrats had been looking likely to win the vote and end more than 50 years of nearly unbroken rule by unpopular Prime Minister Taro Aso's Liberal Democratic Party (LDP).
On Saturday, Ozawa repeated that he would not step down, Japan's Jiji wire reported. "I don't expect to get indicted or to go to court," Jiji quoted him as saying.
But the Mainichi poll showed 57 percent of respondents said Ozawa should step down as party leader, while 33 percent said Ozawa's resignation was unnecessary.
Democrats secretary-general Yukio Hatoyama defended Ozawa but acknowledged that pressure on him to quit would grow if public support for the party fell sharply or if prosecutors found new evidence against the aide.
"I have no intention of saying that there won't be questions over whether he should resign or not," Hatoyama told public broadcaster NHK on Sunday.
"But ... it's only natural for us to support him and we will continue to do so," Hatoyama said. (Reporting by Chikafumi Hodo and Chisa Fujioka; Editing by Paul Tait)