NEW YORK - Superstorm Sandy slammed into the New Jersey coastline with 80 mph winds Monday night and hurled an unprecedented 13-foot surge of seawater at New York City, threatening its subways and the electrical system that powers Wall Street.
At least four deaths were blamed on the storm, and the presidential campaign ground to a halt a week before Election Day. Sandy knocked out power to at least 3.1 million people, and New York's main utility said large sections of Manhattan had been plunged into darkness by the storm. Water pressed into the island from three sides.
The storm washed away part of the Atlantic City boardwalk, putting the presidential campaign on hold and threatened to cripple Wall Street and the New York subway system with an epic surge of seawater.
The National Hurricane Center said Monday evening that Sandy is a post-tropical storm and losing strength but still has sustained winds at 85 mph.
The center says storm surge reached heights of 12.4 feet at Kings Point, N.Y.
One person died in a storm-related traffic accident in Maryland, and a Pennsylvania man fell from a tree while trimming branches in preparation for the hurricane.
As it drew near, Sandy moved closer to converging with two cold-weather systems to form a hellish superstorm of snow, rain and wind. Forecasters warned of 20-foot waves bashing into the Chicago lakefront and up to 3 feet of snow in West Virginia.
Airlines canceled 10,000 flights, disrupting the plans of travelers all over the world, and storm damage was projected at $10 billion to $20 billion, meaning it could prove to be one of the costliest natural disasters in U.S. history.
Interactive: Superstorm heads to the Northeast
"This is the worst-case scenario," said Louis Uccellini, environmental prediction chief for the National Oceanic and Atmospheric Administration.
Because the storm is so big, with tropical storm-force winds extending almost 500 miles from its center, it could upend daily life for big cities and small towns alike across the Northeast — including Washington, Baltimore, Philadelphia, New York and Boston — and as far west as the Great Lakes. Up to 3 feet of snow was forecast for the West Virginia mountains.
"I think this one's going to do us in," said Mark Palazzolo, who boarded up his bait-and-tackle shop in Point Pleasant Beach, N.J., with the same wood he used in past storms, crossing out the names of Hurricanes Isaac and Irene and spray-painting "Sandy" next to them.
President Barack Obama declared emergencies in Massachusetts, Connecticut, Rhode Island, New York, New Jersey and Pennsylvania, authorizing federal relief work to begin well ahead of time. He promised the government would "respond big and respond fast" after the storm hits.
Sandy, a Category 1 hurricane with sustained winds of 85 mph early Monday, was blamed for 65 deaths in the Caribbean before it began traveling northward, parallel to the Eastern Seaboard.
About 90 miles off Cape Hatteras, N.C., the Coast Guard rescued 14 crew members by helicopter from a replica of the 18th-century tall ship made famous in the movie "Mutiny on the Bounty." The Coast Guard searched for two other crew members.
The rescued had donned survival suits and life jackets and boarded two lifeboats after the ship began taking on water. They were plucked from 18-foot seas just before sunrise.
Maryland Gov. Martin O'Malley said a fishing pier in the beach resort of Ocean City, not far from a popular boardwalk and amusement park, was "half-gone." The area had been ordered evacuated on Sunday.
Water was already a foot deep on the streets of Lindenhurst, N.Y., along the southern edge of Long Island, and the canals around the island's Great South Bay were bulging two hours before high tide. Gale-force winds blew overnight over coastal North Carolina, southeastern Virginia, the Delmarva Peninsula and coastal New Jersey.
The major American stock exchanges closed for the day, the first unplanned shutdown since the Sept. 11 attacks in 2001. The floor of the NYSE, typically bustling with traders on a Monday morning, fell within the city's mandatory evacuation zone. The United Nations canceled all meetings at its New York headquarters.
New York called off school for the city's 1.1 million students, and the more than 5 million people who depend on its transit network every day were left without a way to get around. Most planned to stay inside anyway.
New Jersey Gov. Chris Christie was typically blunt: "Don't be stupid. Get out."
The storm bore down barely a week before the presidential election. Wary of being seen as putting political pursuits ahead of public safety, Obama and Republican nominee Mitt Romney reshuffled their campaign plans.
Craig Fugate, chief of the Federal Emergency Management Agency, said FEMA teams were deployed from North Carolina to Maine and as far inland as West Virginia, bringing generators and basic supplies that will be needed in the storm's aftermath.
Pennsylvania's largest utilities brought in hundreds of line-repair and tree-trimming crews. In New Jersey, where utilities were widely criticized last year for slow responses after the remnants of storms Irene and Lee, authorities promised a better performance. Hundreds of homes and businesses were already without electricity early Monday.