CELINA, Ohio — Republican presidential candidate Mitt Romney and President Barack Obama frantically sought to close the deal with voters with precious few days left in an incredibly close race as this year’s October surprise — an unprecedented storm menacing the East Coast — wreaked havoc on their best-laid plans.

Ever mindful of his narrow path to the requisite 270 electoral votes, Romney looked to expand his map, weighing an intensified effort in traditionally left-leaning Minnesota. Obama sought to defend historically Democratic turf as the race tightened heading into the final week.

Wary of being seen as putting their political pursuits ahead of public safety, the two White House hopefuls reshuffled their campaign plans as the storm approached.

Both candidates were loath to forfeit face time with voters in battleground states like Virginia that are likely to be afflicted when Hurricane Sandy, a winter storm and a cold front collide to form a freak hybrid storm.

“The storm will throw havoc into the race,” said Sen. Mark Warner, D-Va.

Obama, preparing to depart for Florida Sunday, a day early to beat the storm, got an update from disaster relief officials before speaking by phone to affected governors and mayors.

“Anything they need, we will be there,” Obama said. “And we are going to cut through red tape. We are not going to get bogged down with a lot of rules. We want to make sure that we are anticipating and leaning forward.”

An opportunity for Obama to demonstrate steady leadership in the face of crisis was offset by the risk that the federal government, as in past emergencies, could be faulted for an ineffective response, with the president left to take the fall.

Obama canceled campaign stops today in Virginia and Tuesday in Colorado to monitor the storm but planned to go forward with other events today in Florida and Ohio, with former President Bill Clinton at his side. He planned to return to Ohio on Wednesday with stops in Cincinnati and Akron, followed by a Thursday swing through Springfield, Ohio, Boulder, Colo., and Las Vegas.

Romney nixed three stops in up-for-grabs Virginia on Sunday, opting instead to campaign with running mate Paul Ryan in Ohio before heading today to Wisconsin, where Romney has chipped away at Obama’s lead.

“I know that right now some people in the country are a little nervous about a storm about to hit the coast, and our thoughts and prayers are with people who will find themselves in harm’s way,” Romney told several hundred supporters crowded into a field house at the University of Findlay, the second of three Sunday rallies.

Romney’s campaign confirmed Sunday that he would not travel to New Hampshire on Tuesday as planned. The campaign already canceled an event today in New Hampshire featuring Romney’s wife, Ann. Advisers say further travel changes are likely as they monitor the storm’s progress.

Vice President Joe Biden canceled an event in New Hampshire. “The last thing the president and I want to do is get in the way of anything. The most important thing is health and safety,” Biden said.

Ryan planned to leave Ohio at midday for three stops in Florida. His Tuesday schedule, however, shifted him to stops in Colorado instead of Virginia.

The prospect that bad weather could hinder early voting and get-out-the-vote efforts is vexing to both Obama and Romney.

“Obviously, we want unfettered access to the polls, because we think the more people that come out, the better we’re going to do,” said David Axelrod, a top adviser to Obama’s campaign. “To the extent that it makes it harder, that’s a source of concern.”