Japan's ruling conservative party suffered a crushing defeat in elections Sunday as voters overwhelmingly cast their ballots in favor of a left-of-center opposition camp that has promised to rebuild the economy and breathe new life into the country after 54 years of virtual one-party rule, media projections said. The opposition Democratic Party of Japan was set to win 300 of the 480 seats in the lower house of parliament, ousting the Liberal Democrats, who have governed Japan for all but 11 months since 1955, according to projections by all major Japanese TV networks. National broadcaster NHK, using projections based on exit polls of roughly 400,000 voters, said the Democratic Party was set to win 300 seats and the Liberal Democrats only about 100. Official results were expected early Monday. As voting closed Sunday night, officials said turnout was high, despite an approaching typhoon, indicating the intense level of public interest the hotly contested campaigns have generated, The Associated Press reported. The loss by the Liberal Democrats would open the way for the Democratic Party of Japan, headed by Yukio Hatoyama, to oust Prime Minister Taro Aso and establish a new Cabinet, possibly within the next few weeks.