Nearly a million people in New York state remain without power after Storm Sandy, as frustration grows over the slow pace of recovery.
US President Barack Obama said restoring power was "critical for us".
Mayor Michael Bloomberg lashed out at Long Island's power utility, saying it had not acted "aggressively enough" to resupply areas left in the dark.
Officials in storm-hit states are also checking whether polling stations can open for Tuesday's presidential vote.
At least 106 deaths have been blamed on Sandy in the US, 40 of them in New York City.
The death toll was revised upwards as state officials released new figures on Saturday afternoon. The death toll in the state of New Jersey was put at 22.
The storm had also killed 69 people as it swept across the Caribbean last week.
Sandy-related power cuts were still affecting some 2.5 million customers in the US early on Saturday, according to the US Department of Energy's Office of Electricity Delivery and Energy Reliability, quoted by Reuters.
That was down from 3.5 million on Friday.
In New Jersey, 32% of customers remained without power, the report said.
Power has been restored to most of Manhattan but other parts of New York City are still without electricity.
Approximately 450,000 customers of the Long Island Power Authority (Lipa) were still without power on Saturday, the utility said.
Mayor Bloomberg criticised Lipa for making inadequate progress in restoring power, particularly in the Rockaways, a series of beachfront neighbourhoods hard hit by the storm.
In New York City and Westchester County, about 275,000 customers of the Consolidated Edison utility company were still cut off as of 07:30 on Saturday (11:30 GMT).
Eighty per cent of the subway system was back in service, New York state governor Andrew Cuomo said on Saturday.
And he said help was on the way to ease petrol shortages.
Eight million gallons (30m litres) of fuel had been delivered, while another 28 million would arrive in the next few days, Mr Cuomo said.
In New Jersey, Governor Chris Christie declared a limited state of energy emergency from noon on Saturday in 12 northern counties.
Vehicles with number plates ending in an odd number can only fill up on odd-numbered dates, and the same for evens.
Three days ahead of the US election, President Obama warned the recovery process would be "difficult and painful".
He praised the US military for bringing equipment and personnel from as far away as California to help with relief efforts.
Restoring power was the first priority, Mr Obama said, especially with the weather getting colder.
The New York marathon, due to take place on Sunday, was cancelled on Friday by Mayor Michael Bloomberg, who said he did not want "a cloud to hang over the race or its participants".
He had previously insisted that the race - in which about 40,000 runners were due to take part - should go ahead.
The storm has also set back preparations for voting on Tuesday.
Nassau County, which covers a large part of Long Island, said Sandy had affected its ability to use some of its polling sites.
Without power, "using electronic voting machines will be really problematic," Democratic election commissioner William Biamonte told the Bloomberg news agency.
"We don't have an assessment of where we are" because officials "can't get an answer of when power is going to be turned on," he said.
Election boards in storm-hit areas of New York state are assessing all their polling sites to decide which ones will be able to operate, state election board spokesman John Conklin told Reuters.
Polling sites may not open in every voting precinct but will be open in as many as possible, he said.
"If you have to move a site, you don't want to move it too far because you don't want to disenfranchise people," he told Reuters.