Widespread gasoline shortages became the latest post-Sandy crisis as Northeast U.S. officials feared they might not be able to keep emergency vehicles running.
At the same time the U.S. death toll attributed to Hurricane Sandy reached at least 90, including 40 in New York City, authorities said.
Among the bodies found in New York City Thursday were two boys, 2 and 4, who were torn from their mother by raging floodwaters on the rural borough of Staten Island Monday night.
Power was restored early Friday to about half the 10 million households and businesses that lost electricity, the Edison Electric Institute utility trade group said.
About 43 percent of New Jersey customers and 16 percent in New York state remained without electricity, officials said.
All of Manhattan was expected to have lights by Saturday, utility Consolidated Edison said. Outer-borough neighborhoods served by overhead lines would likely not have power for at least another week, New York City Mayor Michael Bloomberg said.
New York City transit bottlenecks eased with the reopening of some subways, but most transit in New Jersey was still down, although New Jersey Transit began limited commuter rail service to and from New York's Pennsylvania Station Friday.
Amtrak resumed southbound train service from Penn Station Thursday night and limited service to Boston Friday.
The gasoline situation has quickly shifted from enduring mile-long lines for gas stations to no gasoline at all because Sandy crippled oil companies' ability to deliver fuel, officials said.
Oil tankers can't use the New York or New Jersey harbors, and pipeline shipments from the U.S. Gulf Coast and New Jersey refinery production have been stopped, they said.
AAA said roughly 60 percent of stations it monitors in New Jersey and 70 percent on Long Island were closed.
New Jersey Gov. Chris Christie said Thursday President Barack Obama sent 250,000 gallons of gas and 500,000 gallons of diesel fuel to the state through the Defense Department, and he pledged more if needed.
Paterson, N.J., police said if they would not negotiate emergency contracts for gas soon, they would have to begin siphoning gasoline from other city vehicles to keep police cruisers running, The New York Times reported.
In New York City, the Taxi and Limousine Commission, which licenses city cabs, warned of a taxi shortage Friday because of the fuel scarcity, the Times said.
City officials told the newspaper they reached an agreement with a major oil supplier Thursday night that would ensure emergency vehicles could continue running. They included sanitation trucks and parks department equipment to clean up downed trees as emergency vehicles in addition to fire and police.
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 1-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 NBC.com.
Channels not owned by the company will be allowed to carry the concert, broadcast from NBC facilities in New York's Rockefeller Center and hosted by Matt Lauer of NBC's "Today" show.