* Gas lines reminiscent of shortage in 1970s
NYC marathon canceled after complaints from residents
* Human and economic costs mounting; death toll passes 100
* 3.5 million homes and businesses still without power
* Springsteen, Bon Jovi, Sting sing to aid victims
By Edith Honan and Michelle Nichols
NEW YORK, Nov 2 (Reuters) - Tempers frayed in long gas lines and millions were still without electricity across the U.S. Northeast on Friday as the death toll from superstorm Sandy hit 102 and crews searched for more victims in devastated communities in New York and New Jersey.
The U.S. government moved to ease the fuel crunch by tapping strategic reserves and buying millions of gallons of gasoline and diesel to be trucked to storm-damaged areas.
With the U.S. presidential election four days away, television and newspaper images of angry storm victims could affect the campaign. President Barack Obama, locked in a tight race with Republican rival Mitt Romney, has so far generally received praise for his handling of the storm.
New York City canceled its annual marathon in the face of mounting anger as utilities restored power to about a million East Coast homes and businesses but still had about 3.5 million customers in the dark four days after Sandy hit the U.S. coast.
New Jersey natives Bruce Springsteen and Jon Bon Jovi, along with Sting and a host of others, staged a televised benefit concert on Friday to raise money for victims of Sandy.
The massive storm, which combined a Caribbean hurricane with another powerful weather system, b rought 80 mile-per-hour (130-kph) winds and a record surge of seawater to Manhattan, Staten Island and coastal towns on Monday, sweeping homes from their foundations, shattering piers and swamping subway tunnels.
Forty-one died in New York City, about half of them in Staten Island, which was overrun by a wall of water.
Acute gasoline shortages led to long lines and short tempers across the region. In a move to ease the shortage, the Obama administration directed the Defense Logistics Agency to buy up to 12 million gallons (45 million liters) of unleaded fuel and 10 million gallons (38 million liters) of diesel for distribution to areas affected by Sandy.
The government also waived rules that barred foreign-flagged ships from taking gas, diesel and other products from the Gulf of Mexico to Northeast ports, and said it would tap strategic reserves for diesel for the Defense Department to distribute to emergency responders.
``There should be a real change in conditions and people should see it quickly,'' New York Governor Andrew Cuomo said.
Starting before dawn on Friday, long lines of cars snaked around gasoline stations in scenes reminiscent of the energy shortage of the 1970s. Some of the lines stretched for miles.
``It's a catastrophe,'' said Anthony Ennab, a 21-year-old student, as he waited in line at a Staten Island gas station with a container. ``If I had an emergency, I would have no gas.''
Police were in place at many locations to keep the peace between frustrated drivers. On Thursday, a man who attempted to cut in line was charged with threatening another driver with a gun in the borough of Queens.
Less than half of all gas stations in New York City, Long Island and New Jersey operated on Thursday because of power outages and limited supplies.
New Jersey Governor Chris Christie ordered gas rationing in 12 counties to begin on Saturday.
'BREAKS YOUR HEART'
Sandy started as a late-season hurricane in the Caribbean, where it killed 69 people. At its peak, it stretched from the Carolinas to Connecticut and was the largest storm by area to hit the United States in decades.
New York Mayor Michael Bloomberg said he had spoken to the father of two boys, aged 2 and 4, who were swept from their mother's arms as she tried to escape rising waters on Staten Island. Their father is a sanitation worker and was helping the city respond to the storm when it happened, Bloomberg said.
``It just breaks your heart to even think about it,'' Bloomberg said on Friday. ``While life in much of our city is getting back to normal, for New Yorkers that have lost loved ones, the storm left a wound that I think will never heal.''
Search crews scoured beaches and went house-to-house in Staten Island and other neighborhoods in New York and New Jersey looking for bodies.
In Brooklyn's Coney Island, home to a large Russian immigrant community, Anna Ladd's basement still was swamped and she had no power or gas. Ladd, 62, has applied to the government for help but was wary of what aid, if any, she would receive.
``We have a saying in Russia - when someone promises something, you have to wait three more years until they deliver,'' she said.
U.S. Secretary of Homeland Security Janet Napolitano visited Staten Island on Friday amid angry assertions by some residents that the New York City borough had been ignored.
``A lot of people are hurting and we want to work through the next days and hours to get people on their feet as quickly as possible,'' Napolitano told reporters.
'CONTROVERSY AND DIVISION'
Bloomberg reversed an earlier decision to go ahead with the marathon, which was expected to draw more than 40,000 runners, after rising criticism from residents who said the city should focus on recovery. He said the race had become a source of ``controversy and division.''
Runner Arthur Sorenson, 51, expressed disappointment at the news but said he would put his energy into fixing his Long Island home, which was swamped by Sandy's storm surge.
``All the nasty things that were written and tweeted. It's a race, people!'' Sorenson said. ``I just wonder if all the people who opposed the marathon so much will use that energy for good.''
But Michael Cremer, 45, a benefits consultant, said before the cancellation was announced that the marathon had become a ``symbol of insensitivity'' to Staten Island.
``Staten Islanders feel like the forgotten people,'' Cremer said. ``The thing about the marathon is just mind-boggling and people here are just extremely angry. ... The insensitivity of Mayor Bloomberg is just unbelievable.''
Much of lower Manhattan still lacked power and subway service on Friday, while midtown and uptown Manhattan were close to normal. Power was expected to be restored throughout Manhattan by Saturday, but it could be a week or more in suburbs and more distant towns along the coast.
Disaster modeling company Eqecat estimated Sandy caused up to $20 billion in insured losses and $50 billion in economic losses, double its previous forecast.
At the high end of the range, Sandy would rank as the fourth costliest U.S. catastrophe, according to the Insurance Information Institute, behind Hurricane Katrina in 2005, the Sept. 11, 2001, attacks and Hurricane Andrew in 1992.