Fuel shortages and difficulties in restoring power are hampering efforts to restore normality to parts of the US north-east in the wake of Storm Sandy.
Fights broke out at petrol stations in New York and New Jersey, and power suppliers warned some areas might not have electricity until 11 November.
Anger is also rising in New York's Staten Island, with some residents saying they had been forgotten.
More than 90 deaths in the US have now been blamed on Sandy.
The cost of the storm to the US is now put at about $50bn (£31bn).
Meanwhile, New York Mayor Michael Bloomberg has endorsed President Barack Obama for next week's presidential election, saying Storm Sandy had highlighted climate change, and that only one candidate saw this as an "urgent problem".
Residents and workers of areas affected by Storm Sandy will wake on Friday to continued problems of transportation, lack of electricity and a dearth of fuel.
At many petrol stations there have been long lines of cars and of people carrying jerry cans.
One owner of a fuel station in New Jersey told the New York Times he had been pumping petrol for 36 hours. He said he had to call the police and turn off the pumps temporarily as tempers among customers rose.
There were reports of sharp price increases by some suppliers.
Well over half of petrol stations in New Jersey and in New York City remain closed.
Power officials hope to restore electricity to all of Manhattan and more areas on Brooklyn by Saturday, with more underground lines opening.
Train fares remain free on Friday and a ban on cars with fewer than three people inside will stay in place in Manhattan on Friday.
But Consolidated Edison, the power company serving New York, warned that some areas of the city would be blacked out until 11 November.
Almost 45% of customers in New Jersey and some 15% in New York State remain without electricity.
New York West Village resident Rosemarie Zurlo told Associated Press she was abandoning her flat temporarily and heading to Brooklyn: "I'm leaving because I'm freezing. My apartment is ice cold. Everybody's tired of it."
Some 19 people are now known to have died in the south-western New York City borough of Staten Island.
The storm swamped the low-lying district with tidal surges, lifting whole houses off their foundations.
Anger is rising there at the delay in bringing aid, with litter piling up and residents picking through the debris of storm-ravaged homes.
James Molinaro, the borough's president, complained the American Red Cross was "nowhere to be found".
He said: "We have hundreds of people in shelters. Many of them, when the shelters close, have nowhere to go because their homes are destroyed. These are not homeless people. They're homeless now."
One resident, Theresa Connor, told Reuters her neighbourhood had been "annihilated".
"They forgot about us... And Bloomberg said New York is fine. The marathon is on."
New York City councilman James Oddo said: "If they take one first responder from Staten Island to cover this marathon, I will scream."
Secretary of Homeland Security Janet Napolitano and a senior Federal Emergency Management Agency (Fema) official, Richard Serino, will visit the borough on Friday.
Mr Bloomberg defended the decision to hold the race, saying: "This city is a city where we have to go on."
National Guardsmen and community groups are being deployed in New York and New Jersey amid mounting fears for elderly residents stranded in their homes.
Aid worker Monique George told AP: "In some cases, they hadn't talked to folks in a few days. They haven't even seen anybody because the neighbours evacuated."
In Hoboken, New Jersey, some 20,000 people are still trapped in their homes as floodwaters slowly recede.
Officials warned residents not to walk in water polluted with sewage and chemicals.
Sandy arrived on the US Atlantic coast on Monday night, bringing hurricane-strength winds, flooding and blackouts.
The number of dead in the US now exceeds the toll from the Caribbean, where 69 people were killed by Sandy.
Meanwhile, campaigning for Tuesday's US presidential election - suspended earlier in the week - has fully resumed.
Mr Obama received a boost with the endorsement of Mr Bloomberg.
Of the two candidates, the New York mayor said, "one sees climate change as an urgent problem that threatens our planet; one does not".
"I want our president to place scientific evidence and risk management above electoral politics."
Both candidates are now awaiting the final key economic figures to be released before Tuesday's election.
The US Labor Department will announce the latest job figures at 12:30 GMT, and they may play a key role in the final days of campaigning.
Mr Obama and Republican challenger Mitt Romney are both engaged in a final push for votes, particularly in eight battleground states.
Polls show Mr Obama holds a slight lead in five of these so-called swing states - Ohio, Wisconsin, Iowa, Nevada and New Hampshire - while Mr Romney leads slightly in Florida. Virginia and Colorado are effectively tied.
A Reuters/Ipsos national online poll on Thursday showed Mr Obama on 47% and Mr Romney on 46%.
Mr Obama visited four swing states on Thursday.
Mr Romney told supporters in Virginia: "This is a time for greatness. This is a time for big change, for real change."