Atlantic City Electric says nearly 20,353 homes and businesses were still without service early Thursday. That's down from about 206,000 at the height of the storm.
Atlantic and Cumberland counties were hardest hit by the severe thunderstorms, which contained strong winds and lightning.
Utility officials say the vast majority of customers should have power restored by midnight Wednesday, though it could take until Friday for all customers to have their power back.
Those without power are facing another stretch of hot, humid weather. Highs temperatures are expected to remain in the 90s all week and may hit 100 degrees on Saturday.