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Dave Dixon and his wife are bunking with friends after losing power in a snow-and-ice storm that caused more than a million U.S. outages -- the vast majority of them in a single state, Pennsylvania.

The storm has long since cleared out, but its effects are expected to linger for days as utility crews work feverishly to restore power to hundreds of thousands of Pennsylvania residents left in the dark and cold. One official likened the damage to what you'd expect to see from a hurricane.

Pennsylvania's utility regulator says 451,000 customers remain without power as of 11 a.m.

Pennsylvania Utility Commission spokeswoman Jennifer Kocher said the figure is down by about 300,000 from 24 hours earlier.

The crippling ice storm took down trees and limbs across a 100-mile-wide region. Shelters were in operation as temperatures dipped well below freezing.

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    Pennsylvania Gov. Tom Corbett warned the freezing temperatures could create hazardous driving conditions Thursday. The governor issued a disaster emergency proclamation Wednesday which freed up state agencies to use all available resources and personnel.

    The Northeast's second winter storm of the week dumped more than a foot of snow in some states, forcing schools, businesses and government offices to close, snarling air travel and sending cars and trucks sliding on slippery roads and highways -- an all-too-familiar litany of misery in a winter where the storms seem to be tripping over each other.

    What made this one stand out -- and caused all those outages -- was the thick coating of ice it left on trees and power lines.

    Maryland reported about 69,000 customers without power Thursday. Tens of thousands of New Jersey residents also lacked electricity.

    "The damage that we are seeing in the field with the number of trees down, not only on lines but blocking roads and more, presents a number of logistical issues," said Pennsylvania Public Utility Commission spokeswoman Jennifer Kocher. "This damage is very similar to what we see during hurricanes."

    At its height, the storm knocked out power to nearly 849,000 customers in Pennsylvania, most of them in the counties around Philadelphia. Though sizeable, it's still less than the nearly 1.8 million that were left without power after Superstorm Sandy in 2012.

    While some homeowners fired up generators, others, like the Dixons, are relying on the generosity of others to power them through.

    "If we wear out our welcome, we'll get a hotel," said Dixon, whose home in the Philadelphia suburbs went dark at 6 a.m. Wednesday.

    In Wyncote, a town just north of Philadelphia, Hannah Reimer took to Facebook to ask for a kerosene heater and recommendations on where to buy the fuel.

    "And it worked! Someone from my church, who has power, has a kerosene heater and my husband is picking it up now," she said Wednesday night.

    Reimer and her husband then planned to pay it forward, inviting their neighbors to spend the night.

    "Our neighbors don't have heat, either," she said. "Or a kerosene heater."

    Thousands of utility workers descended on the Philadelphia suburbs to get the lights back on.

    Several hospitals were running on backup generators. Most decided to cancel elective surgeries and out-patient testing.

    Dr. John Kelly, chief of staff at Abington Memorial Hospital outside Philadelphia, one of the affected facilities, said critical staff needed for any emergencies would be staying overnight. He said the hospital had plenty of fuel and food.

    The American Red Cross opened three shelters in southeastern Pennsylvania and stood ready to open more.

    "We've been told to be prepared for four to six days. We are gathering staff and volunteers for up to a week," said Red Cross spokesman Dave Schrader.

    The Associated Press contributed to this report.