Aso said that he needed more time to implement economic measures aimed at pulling the country out of its economic slump, but opinion polls have indicated that voters are unlikely to give it to him.
Opinion poll lead
Surveys in major newspapers, including the Mainichi and the Asahi, said that the Democratic Party of Japan (DPJ) of Yukio Hatoyama was likely to win more than 320 seats in the 480-member lower house of parliament.
Hatoyama travelled to the city of Sakai in western Japan on Saturday where he repeated his call for voters to support change.
"At last, it is the election tomorrow, one that we will be able to tell the next generation changed Japanese history," he said.
The LDP has ruled power for all but 10 months since it was founded in 1955, but the DPJ already controls the less powerful upper house of parliament following elections in 2007.
Under a mantra of "Putting People's Lives First", the DPJ has offered a platform heavy on social-welfare initiatives, including cash handouts for job seekers in training and families with children.
"We will stop bureaucracy-led politics and draft policies through dialogue with the Japanese people," Hatoyama said.
But Jeff Kingston, director of Asian Studies at Temple University in Japan, said that voters seemed set to vote for "change that they don't believe in and for a leader they are not all that crazy about".
"Polls show that only 25 per cent of people actually believe that the DPJ is actually going to lead the country in the right direction," he told Al Jazeera from Tokyo.
"Everybody is so deeply frustrated with the ruling party that they are desperate for change. The vote for the DPJ is not a mandate on their platform; it is just a verdict on the hopelesness of the current situation."
Hatoyama will face tough challenges if he does succeed with the nation suffering its worst unemployment since the second world war and lingering deflation.