The polls — which set the stage for the more important presidential vote in July — opened first in the easternmost province of Papau.
Around 171 million Indonesians were choosing Thursday among 38 parties vying for spots in the 560-seat legislature.
A party or coalition that wins a fifth of the seats — or 25 percent of the popular vote — can nominate a presidential candidate.
President Susilo Bambang Yudhoyono´s Democratic Party is expected to lead.
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