Exit polls in Japan's general election indicate that the ruling Liberal Democratic Party, which has been in power for almost 50 years, is headed for defeat.
The poll by one of Japan's main broadcasters indicates that the centre-left Democratic Party of Japan is on track for a landslide win with around 315 of the 480 seats in Parliament.
Voters frustrated with the government's handling of Japan's worst post-war recession were set to punish embattled Prime Minister Taro Aso and force the Liberal Democratic Party (LDP) from office.
An opposition win would see the Mr Hatoyama, 62, take over as prime minister, charged with steering the world's number two economy through the global downturn as it struggles with record unemployment.
Mr Hatoyama, a US-trained engineering scholar, campaigned on a promise of change and people-centred politics against the business-friendly LDP, headed by Mr Aso.
The DPJ already controls the upper house with the support of smaller parties, including the Social Democrats.
A two-thirds majority in the lower house would give the party sufficient numbers to push through legislation.
Voter turnout by the afternoon was marginally higher than in polls four years ago.
