The 88 U.S. deaths attributed to Sandy brought the storm's overall death toll to 157, with 67 dead in the Caribbean and two confirmed dead in Canada, CNN reported.
At least 37 people were killed in New York City. At least six people died in New Jersey, and officials said they feared the toll would rise as additional home searches were conducted.
The National Weather Service said Thursday a nor'easter could develop next week over the mid-Atlantic states into New England, but the storm was not expected to be as strong as Sandy, CNN reported.
An estimated 4.9 million households and businesses remained without power across the Northeast -- an estimated 530,000 of them in New York -- and authorities warned it could take a week or more to restore electricity for many. ABC News reported Con Ed expects to have all power restored in Manhattan by Saturday.
Con Edison said Thursday it expects to restore service by the end of next week to "the vast majority" of those who lost power in New York City and Westchester County due to superstorm Sandy.
In a news release, the utility said it could take at least another week to restore service to all customers.
An estimated 900,000 Con Ed customers lost power due to the storm. The company said service had been restored to about 250,000 customers by 11 a.m. Thursday.
The storm led to power failures in at least 17 states.
During President Barack Obama's flight to Wisconsin for a campaign event Thursday, White House press secretary Jay Carney told reporters aboard Air Force the president would maintain contact with Federal Emergency Management Administrator Craig Fugate and "the rest of his team to ensure that bureaucracy and red tape are not impeding efforts to respond to communities recovering from the storm."
Carney said Obama would conduct conference calls during the day with local elected officials in areas affected by the storm.
The White House announced Secretary of Homeland Security Janet Napolitano will travel to Connecticut and New York to meet with state and local officials, and inspect response and recovery operations.
Subways and buses rolled again in some parts of New York City Thursday and mandatory water restrictions were in effect across New Jersey after Sandy.
Meanwhile, Bruce Springsteen and Jon Bon Jovi of hard-hit New Jersey and Billy Joel of New York's badly damaged Long Island are scheduled to perform in a one-hour telecast benefit concert for victims of Sandy Friday.
The 8 p.m. EDT "Hurricane Sandy: Coming Together" concert -- which is also to include Christina Aguilera, Sting, comedian Jimmy Fallon and NBC News anchor Brian Williams -- will benefit the American Red Cross, NBCUniversal Media said.
The event, which will be taped-delayed in the West, will be shown on NBC and NBCUniversal cable stations Bravo, CNBC, MSNBC, E! Entertainment Television, G4, Syfy, Style Network and USA Network, NBCUniversal said. It will also be streamed live on the NBC.com website.
Channels not owned by the company will be allowed to carry the concert, broadcast from NBC facilities in New York City's Rockefeller Center and hosted by Matt Lauer of NBC's "Today" show.
Service resumed Thursday on 14 of New York's 23 subway lines, but no service was below 34th Street, much of which was still without power. City buses and suburban commuter rail lines also ran with limited service.
All transit fares were eliminated Thursday and Friday after New York Gov. Andrew Cuomo and Connecticut Gov. Dannel P. Malloy authorized the Metropolitan Transit Authority to waive fares Thursday and Friday as an inducement to get people to take mass transit.
Much of New York City faced gridlock. Taxis picked up multiple passengers. Gasoline was increasingly hard to come by -- some cars ran out of gas while waiting for hours in mile-long lines.
New York Mayor Michael Bloomberg ordered Manhattan-bound cars on all bridges except the George Washington Bridge from New Jersey to have at least three occupants from 6 a.m. to midnight Thursday and Friday. Taxis and livery cars were exempt from the restriction.
All four major New York-area airports were in operation, including LaGuardia, which was shut down until Thursday morning because of severe flooding.
The Port Authority of New York and New Jersey said the first plane landing at LaGuardia was a Delta Air Lines flight from Syracuse, N.Y.
Kennedy, Newark and suburban Stewart International Airport were expected to be at full operation Friday, the Port Authority said.
Organizers said the New York City Marathon will be run as scheduled Sunday, CNN reported.
In New Jersey, which bore the brunt of the storm, most mass transit systems remained shut down.
Gov. Chris Christie said mandatory statewide water restrictions were in effect as a result of power outages from Sandy that sapped water-treatment systems.
Any water use that's not essential will not be allowed, he said in announcing the restrictions late Wednesday.
"Maybe take a little bit of a shorter shower," Christie suggested.
About a quarter of the state's population -- more than 2 million people -- remained without power early Thursday, and more than 6,000 were still in shelters, state emergency officials said.
More than 100 municipalities where federal emergencies were declared this week have the lowest ratings from the federal government under a program that rewards communities for trying to minimize flood damage, USA Today reported. The program gives residents of communities that take flood-prevention action higher discounts on their insurance premiums.
Large portions of West Virginia, as well as western Maryland and southwestern Pennsylvania, were digging out from snowfall accumulations of as much as 2-3 feet in some places. Some parts of the region may get several more issues of snow, forecasters said.
Obama viewed the destruction with Christie Wednesday, then met with residents in a community-center shelter set up in Brigantine, 5 miles from Atlantic City.
"The entire country has been watching what's been happening," Obama said. "Everybody knows how hard Jersey has been hit."
Boardwalks along beaches were blown away. Amusement parks, arcades and restaurants were turned to rubble. Barrier island bridges buckled, keeping residents from inspecting property damage, the Times said.
In Hoboken, N.J., a city of about 50,000 across the Hudson River from Manhattan, thousands of residents remained stranded in apartment buildings Thursday, cut off from help by streets still waist-high in contaminated water.
"This is historic," Hoboken Mayor Dawn Zimmer told The Wall Street Journal Wednesday. "We are trying to reach everyone as quickly as we can."