Governor Phil Murphy announced the decision Tuesday, the latest development as the state begins to loosen restrictions that stemmed from the coranavirus outbreak.
The businesses have been among the hardest-hit during the pandemic, and earlier this month, NewsCopter 7 flew over Port Newark, one of the biggest ports in the U.S. for imported vehicles.
Video showed the piers at the port overflowing with new cars, trucks and SUVs that couldn't get to area dealerships.
Showrooms at car dealerships were shut down by the state as the pandemic intensified.
The New Jersey Coalition of Automobile Retailers had been pushing to reopen those showrooms on a limited basis. They say the state has been losing $4.5 million a day in sales tax and motor vehicle fees.
Nationwide, new car demand is expected to drop 27% this year.
The Associated Press contributed to this report.
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