* New York officials consider closing subway lines next week
* Utilities' response to any outages to be closely watched
By Barbara Goldberg
NEW YORK, Oct 26 (Reuters) - Governors up and down the U.S. East Coast declared states of emergency on Friday before a potential pounding from Hurricane Sandy, as authorities urged residents to stock up on food, water and batteries in case the storm lives up to forecasters' worst fears.
From the Carolinas to Maine, municipal authorities kept a close watch on forecasts tracking the shifting path of the fierce "Frankenstorm," which could come ashore on Monday with heavy rain, storm surges and near hurricane-force winds.
In New York City, officials were considering closing down bus and subway lines next week, a step taken only once before - when Hurricane Irene slammed the city in 2011.
New York, North Carolina, Virginia and Maryland declared states of emergency to free up resources. The District of Columbia also declared a state of emergency as the U.S. capital prepared for a possible hit.
Virginia Governor Bob McDonnell urged residents in coastal areas to prepare to evacuate before the storm hits and advised others in the state to stock up on provisions needed to get through any disaster.
"I encourage all Virginians to gather batteries, blankets, water, canned goods and other necessities prior to the anticipated onset of storm conditions," McDonnell said in a statement. "We could see severe weather lasting for 48 hours or more in the state."
The storm's likely impact on Virginia prompted Republican presidential candidate Mitt Romney's campaign to cancel his Sunday night rally in Virginia Beach.
In Pennsylvania, officials warned about the dangers of driving during the storm, especially over roads and bridges already under water.
"Just a few inches of moving water can sweep away the average car," warned the Pennsylvania Emergency Management Agency in a statement. "Turn around, don't drown."
Gusts from the storm's 550-mile (890-km) wind field were being felt in southern Florida on Friday as the slow-moving hurricane that killed at least 41 people in the Caribbean roared toward the United States.
Forecasters dubbed it "Frankenstorm" because three merging weather systems were expected to meld into a single "hybrid" super storm.
Utilities from neighboring inland states readied staging areas so that crews could answer calls for help as they come in from stricken towns and cities along the East Coast.
The utilities' response to outages caused by Hurricane Sandy will be closely watched after they promised to correct problems in restoring electricity lost during Hurricane Irene and last year's freak October snowstorm - the worst outages in Connecticut history.
Massachusetts Energy Secretary Richard Sullivan told a news conference: "They are under strict scrutiny on their response to this particular storm. We are expecting that the level of service is going to be much higher."
Consolidated Edison in New York said it was gearing up for tidal surges that may be worse that during Irene.
"All company personnel and field crews are preparing for high winds, heavy rains and flooding conditions that could wallop electric, gas and steam systems when the storm moves into New York City and Westchester County," Con Ed said in a statement.
The utility pressed customers to heed safety tips regarding downed electrical wires and keeping flashlights at the ready as well as freezers closed during power outages.
Residents offered their own storm-preparation ideas on Facebook, Twitter and through email messages.
"I have a magnetic flashlight that adheres to the fridge. The idea is that, in case of a sudden blackout, we can always find the flashlight which will help us find the candles!" wrote Linda Federico-ó Murchú of Montclair, New Jersey, in response to a friend's Facebook request for tips.
"So, note to self: make sure batteries are fresh. Ditto cellphones charged up," she added.