New Jersey election officials have certified Newark Mayor Cory Booker as the winner of this month's special election to the U.S. Senate.

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The certification means the Democrat can be sworn in to fill the remaining 14 months of the term previously held by the late Frank Lautenberg.

Booker is planning a swearing-in for Thursday. He received 740,742 votes to Republican Steve Lonegan's 593,684, giving him a margin of nearly 12 percentage points.

Six independent candidates each received between 1,000 and 6,000 votes.

Turnout was 25 percent of the eligible voters. That compares with 47 percent in the general election in 2009, when the governor's race was at the top of the ballot.

Gov. Chris Christie faced some criticism for holding the special election 20 days before the general election.

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