TOKYO (AP) - Leaders for Japan's biggest political parties are kicking off the campaign for parliamentary elections to be held in less than two weeks with visits to nuclear crisis-hit Fukushima prefecture.

Nuclear energy and the economy are key issues in the Dec. 16 election, which is widely expected to send Prime Minister Yoshihiko Noda's unpopular Democratic Party of Japan to defeat after three years in power.

The opposition Liberal Democratic Party is leading in the polls, but is unlikely to win a majority of seats in the lower house of parliament.

The most likely outcome of the election is a coalition government whose makeup is far from clear.

Polls show more than 40 percent of voters don't know which party they'll support in the election.

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