TRENTON, N.J. (AP) -- The former mayor of Randolph won the Republican congressional primary Tuesday in a southern New Jersey district where both candidates moved to run.

Jessica Kourkounis, Getty Images

Tom MacArthur will face Democrat and Burlington County Freeholder Aimee Belgard, who easily won a three-way race, in the November general election in the 3rd District, considered the most up-for-grabs among 12 in the state.

The current congressman, former Philadelphia Eagle Jon Runyan, a Republican, is not seeking re-election in the district that cuts across the center of the state from the Philadelphia suburbs to the shore.

MacArthur defeated former Bogota Mayor Steve Lonegan, who last year put up a stronger showing than many expected in a special U.S. Senate election that was ultimately won by Cory Booker.

"We may have lost tonight, but the fight for our conservative values continues," Lonegan said in a statement.

Steve Lonegan (Kena Betancur, Getty Images)

MacArthur, a former insurance executive, outspent Lonegan $2 million to $800,000. Nearly all of MacArthur's money was his own. Lonegan contributed $300,000 to his own campaign.

The 3rd District is one of three with open seats in the general election.

A state legislator and brother to one of New Jersey's political powerbrokers won the Democratic nomination in the 1st District.

Sen. Donald Norcoss, the brother of insurance executive George Norcross, will face Republican and former Philadelphia Eagle Garry Cobb in the fall in the heavily Democratic 1st District. Norcross beat two rivals, including Logan Township Mayor Frank Minor, for a chance at the suburban Philadelphia seat.

The seat had been held for more than two decades by Rep. Rob Andrews, who resigned in February.

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