TRENTON, N.J (WPVI) -- Democratic former national security aide to Barack Obama Andy Kim has defeated two-term Republican incumbent Rep. Tom MacArthur in New Jersey's 3rd District.Kim upset MacArthur in the hotly contested southern New Jersey district, widening the Democrats' edge in the House.The U.S. House historian's database shows he's the first Asian-American elected from New Jersey. Kim has never run for or served in elected office before.The Associated Press called the race Wednesday.The district last elected a Democrat in 2008.MacArthur was an ally of the president's but stressed his independence as well.He was the only New Jersey congressmen to vote for the 2017 tax overhaul and backed repeal of the Affordable Care Act.New Jersey will have just one Republican out of 12 seats in the next Congress.------