As hundreds of thousands of Big Apple residents suffer in homes left without power by Hurricane Sandy, two massive generators are being run 24/7 in Central Park — to juice a media tent for Sunday’s New York City Marathon.

And a third “backup” unit sits idle, in case one of the generators fails.

EDITORIAL: Marathon is power mad!

The three diesel-powered generators crank out 800 kilowatts — enough to power 400 homes in ravaged areas like Staten Island, the Rockaways and downtown Manhattan.

As of Friday morning, five generators sat outside of the park along with electrical stations and transformers.

In addition to the generators, a food services truck dropped off hundreds of cases of water, sparking angered responses from hurricane victims.

“I am from Coney Island where everything is flooded and underwater,” Yelena Gomelsky, 65, said. “I live 1 block from the ocean where everything is floating. “[Seeing the generators and water] makes me feel so bad. People have no food, no water, nothing.

“They should make all of these runners bring food and water to people’s houses who need it. They should bring all of these generators to buildings where old people live and give them power.”

Joan Wacks, whose Staten Island waterfront condo was swamped with 4 feet of water, predicted authorities will still be recovering bodies when the estimated 40,000 runners from around the world hit the streets Sunday, and she called the mayor “tone deaf.”

“He is clueless without a paddle to the reality of what everyone else is dealing with,” she said. “If there are any resources being put toward the marathon, that’s wrong. I’m sorry, that’s wrong.” She added: “We totally understand the public relations aspect, to show everyone survived. But this is not one of those times.”

Since emergency executive orders have been issued, the governor, mayor — or even President Obama — could take the generators for a more important use, explained Pace University law professor Bennett Gershman.

Such an emergency action would need the approval of the City Council, state Legislature or Congress. And they would have to compensate the owners of the devices.

But plenty in the city wish they had taken such decisive action. After all, New Jersey Gov. Chris Christie postponed Halloween for safety reasons, so Gov. Cuomo or Mayor Bloomberg should issue an executive order for lifesaving generators.

Manhattah Borough Preisdent Scott Stringer voiced his opinion on Friday, saying that the city needs to recognize the suffering following “a tragedy of historic proportions.”

“New Yorkers in Staten Island, the Rockaways, Coney Island and Lower Manhattan are struggling to keep body and soul together, deprived of basic essentials as temperatures drop,” Stringer said.

“For this reason, and after significant deliberation, I believe we should postpone and re-schedule the New York City Marathon in order to focus all of the City’s resources on the crucial task of helping our neighbors recover from this disaster. New Yorkers deserve nothing less than to know that the entire government is focused solely on returning the City and their region back to normalcy.”

Fellow pol Margaret Chin echoed Stringer’s concern.

“We’re struggling here, and we want the city to know that,” Councilwoman Chin of Chinatown said yesterday.

She asked the Office of Emergency Management on Tuesday for a generator to run pumps to get water to stranded seniors.

“They’re telling me there are other priorities,” Chin said.

One hotel on Staten Island has its priorities straight.

Frank Sanchez, the general manager of the Hilton Garden Inn, said he will not honor marathoners’ reservations if it means throwing out storm refugees.

“While we understand they have reservations, we know they are going back to their regular lives in two days. Our neighbors will not have that opportunity,’’ he e-mailed The Post.

The New York Road Runners Club, which organizes the world-famous race, is paying for the generators, which were supplied by Long Island-based On Site Energy for the massive, 80-yard-long tent, which also will be used by runners carbo-loading during a pre-race pasta dinner tomorrow.

Neither would say how much the machines cost, but a Fire Department permit revealed a $37,500 fee to run them constantly through Nov. 6.

“These are our private generators. We are not draining any resources from the city’s plan to recover,” Road Runners spokesman Richard Finn angrily insisted.

Still, Con Ed said yesterday that some of its customers would remain without power for more than a week.

Meanwhile, sources told The Post precious city resources were also being diverted to prepare for the marathon, including more than a dozen NYPD flatbed trucks taken from disaster-relief work at sites including Breezy Point, Queens, where more than 100 homes burned to the ground.

The trucks, normally used to carry metal barricades for parades and other events, had been transporting residents hard hit by the storm.

But they’re all being recalled to get cleaned up so they can bring the barriers that will line the route of the marathon, a police source said.

“People could still use our help,” the source said. “We’re serving a purpose shuttling them back and forth.”

Plans call for up to 100 cops from all around the city to deploy the barricades today.

“You know what this is about? This is all so Bloomberg can stand at the finish line Sunday and tell the world we bounced back,” the source said.

“But these poor people on Breezy, who knows when and if they will bounce back?”

Bloomberg defended the decision to keep the race on track.

“The marathon is not going to redirect any focus. Keep in mind, by Sunday, we’ll have electricity back downtown,” he predicted.

“That will free up an enormous number of police.”

Staten Islander Sue Somma, whose neighbors — John Filipowicz Sr. and his 20-year-old son, John Jr. — drowned in their flooded basement, said, “People don’t realize what other people are going through.

“This is the way we live — with stupid decisions,” she said.

“The city always does these stupid things.”

A veteran police lieutenant noted the National Guard was distributing free food last night at several spots in lower Manhattan — while the administration keeps the marathon a priority.

“How can you run a marathon when you have people starving in Manhattan?” he asked.

Other sources said NYPD and Department of Transportation personnel who had been providing relief on Staten Island were told to drop what they were doing and report to Brooklyn today to get ready for the marathon.

Official race preparations yesterday included closing all lanes on the Staten Island-bound upper level of the Verrazano Bridge for more than an hour of work.

Staten Islander Joseph Masella, 62, called running the marathon “the most ridiculous thing I’ve ever heard.”

“Have some respect for our citizens . . . They’re still finding bodies here,” he fumed.

Staten Island Councilman James Oddo said, “The notion of taking one cop, one first responder, one resource, one asset and diverting it so that they stand at a post to watch runners go by when we’re still searching for bodies? It’s sinful to me!’’

Brooklyn Councilman Vincent Gentile said, “With some neighborhoods still smoldering, I think postponing the marathon would be a better option.”

With AP and additional reporting by Philip Messing, Yoav Gonen, Brian Lewis and Bruce Golding