Paul Beck, Ohio State University professor, describes the importance of winning Ohio, a battleground with a large number of electoral votes. It's a diverse state with liberals and conservatives matching a cross section of the nation.

Hurricane Sandy is barreling toward the East Coast and could deliver the presidential campaign an unpredictable, but impactful, October surprise.

It remains too early to determine precisely where Sandy will make landfall or just how severe the storm might be, but the projections for its path have it aimed toward the mid-Atlantic region, likely impacting hotly-contested battleground states.

Sandy was briefly downgraded from a hurricane to a tropical storm by the NHC early Saturday, but it returned to hurricane strength within a few hours.

Warnings as Sandy heads north

Extensive damage, power outages, and the resulting news coverage could push the election into the background, at least in that region, and could wreak havoc on campaign plans for the final week of the race between President Barack Obama and Republican nominee Mitt Romney.

Travel schedules, television advertising buys, and voter outreach could all be impacted … and in some cases, already have been.

A Romney official said Friday that the campaign is keeping a very close eye on the storm and had already decided to cancel a planned rally on Sunday night in Virginia Beach. Vice President Joe Biden also cancelled a Virginia Beach event on Saturday, and a rally for First Lady Michelle Obama planned for Tuesday at the University of New Hampshire in Durham was also canceled, officials said Friday.

Said the Obama campaign of the change in the vice president's schedule, "This ... is being taken out of an abundance of caution to ensure that all local law enforcement and emergency management resources can stay focused on ensuring the safety of people who might be impacted by the storm."

Slideshow: Sandy barrels through the Caribbean After strong winds and heavy rain washed out bridges and damaged homes in multiple countries, the hurricane looks toward the northeastern U.S. Launch slideshow

It isn't yet clear whether Sandy will affect Obama’s scheduled events with former president Bill Clinton in Florida and Virginia on Monday.

Since March, the two presidential campaigns and outside groups have invested $144 million in radio and TV ads in Virginia, with $27 million spent just in the past two weeks. Virginia ranks third in the amount of presidential campaign advertising, after Ohio and Florida.

If local TV stations in Virginia interrupt their regularly scheduled programming in order to broadcast bulletins and live coverage of the storm’s impact, then a campaign ad which had been booked for a specific time on a specific station would not air.

The station would refund the money paid for the ad, but at this point in the election season, campaigns don’t want their money back -- they want their ads to run.

RELATED: Ad spending on presidential race surpasses $900 million

Of course, even if stations do run those already-booked campaign ads, thousands of Virginia homes might be without power … and millions of dollars in ad buys could be still wasted.

After the intense “derecho” storm swept through the Midwest and Mid-Atlantic region with 70-mile-per-hour winds on June 29, electricity for millions of customers was effectively knocked out.

In some areas around Washington, D.C., power was out for a week. And outages in Virginia due to Sandy could conceivably last into Election Day itself.

Voting requires polling locations which have the lights on and aren't under water, so this storm also raises the question of how election officials are preparing to ensure that balloting isn’t disrupted on Election Day.

Mitt Romney has just wrapped up what his campaign billed a major economic speech, at the heart of his closing arguments. Democratic strategist Elmendorf, Romney campaign economic adviser Vin Weber and The Economist's Greg Ip break it down.

According to Virginia State Board of Elections spokeswoman Nikki Sheridan, the board has been coordinating with the state Department of Emergency Management, the Virginia State Police, the state Department of Transportation, major utility companies, and the 134 voting registrars who administer the election across the state “to monitor the weather situation and, if necessary … act accordingly.”

The board has told local election officials that “unless conditions render the voting process unsafe” for employees and voters, registrars should keep their offices “open and to continue the in-person voting process” already underway in the state.

The final decision whether to close a general registrar’s office “will be made by local authorities or first responders after consultation with your office and electoral board,” the board said.

RELATED: Focusing on Ohio and Colorado

In a press conference Friday afternoon, Virginia Gov. Bob McDonnell, a Romney supporter, said, “There are obviously concerns about making sure we’re ready for Election Day which will only be a week after the departure of this storm.”

He said that the president of Dominion Power, the state’s major power provider, has told him that the utility would add election locations “as a top priority for power restoration in addition to hospitals and schools and so forth, so I think that is prudent as well, but we don’t anticipate adverse election issues at this time.”

The candidates crisscross the country hitting the battleground states trying to lock up key electoral votes and Domenico demonstrates the electronic map to 270.

He said the electric utility had a “well-thought out set of priorities for what to restore” and “at this point I don’t see anything happening that would interfere with the election.”

He also said “I expect both candidates and both parties to monitor the situation and if they think they’re going to be interfering with first responder operations” to cancel their Virginia campaign events. “They’re not going to get coverage and they’re not going to get people coming out (to events) because they’re not going to stand out in the rain so they’d be smart to make alternative plans.”

Ross Goldstein, deputy administrator of the Maryland Board of Elections, said Friday, “We’re in contact with state emergency management. We’ve given utility companies a list of polling locations so that they know where our needs are.”

He added that “all of our voting equipment has battery backup,” but noted that, obviously, electricity would be needed to keep the lights on at polling locations.

As in Virginia, Maryland voters have the option of early voting, beginning in the state on Saturday, with one-to-five polling places per county.

In a conference call on Friday, elections officials in Maryland and eight other East Coast states conferred with Louisiana Commissioner of Elections Angie Rogers to find out what officials in her state have learned from coping with the aftermath of Hurricane Katrina in 2005 and other subsequent storms.

Louisiana Secretary of State Tom Schedler said Friday that contingency plans must be made for both before and after Election Day.

Obama campaign co-chair Kal Penn joins Andrea Mitchell Reports to discuss the youth vote in the 2012 election.

“Number one, before the storm, secure the (voting) equipment, move it if necessary, get it out of harm’s way,” he said.

“Number two, get good information on where your poll workers are going to be, make sure you have their cell numbers and evacuation plans so you can get in touch with them if you’ve moved a precinct," he said.

"Then after the storm, determine if your locations are still viable and usable and if they’re not, make sure you move and consolidate precincts. We did that here in Louisiana with the big mayoral election after Katrina. As long as you have locations, power and equipment or paper ballots -- you can still have the election and go forward," he added.

Schedler said another tip for elections officials in storm-affected areas: “Make sure you have a good relationship with the National Guard in your state. Here in Louisiana we used the National Guard to set up large tents for ‘mega-sites.’ They provided us generators. And think about public restrooms, you may need to bring in some Portalets (portable toilets) when setting up as site like that. You need to anticipate just like you do in any emergency.”

He also suggested that state officials in Sandy's path urge people to vote early.

NBC News’ Garrett Haake contributed to this report.