DAYTON, Ohio: Super storm Sandy is a bona fide disaster impacting millions of Americans, but as floodwaters surge ashore one week from election day, a discomfiting political question emerges.

Which candidate stands to lose the most?

President Barack Obama is in office and the man at the helm. He could sink or swim on his handling of the federal response to such a serious crisis that has already claimed 13 US lives and caused millions in damage.

Mitt Romney, who aims to unseat Obama on November 6, has shown compassion for victims and has called on supporters to help fellow Americans in need, but with no official role in response operations risks appearing left out.

“Right now, with the storm making landfall and affecting as many as 50 million people, the priority has to be on safety and on relief efforts,” a Romney campaign official told AFP late Monday.

“And a lot of campaign decisions have to be made with that in mind.”

The White House offered similar declarations, stressing the “safety and security of Americans” was the top priority and acknowledging that two full days of campaigning could be lost due to the storm.

“We have to focus on not the campaign and not the election, but on making sure that all federal resources are both prepositioned and in place to help states and localities respond to the storm,” Obama spokesman Jay Carney said.

“That's our focus right now.”

But there is an election to win and, with virtually everyone agreeing that the presidential race will go down to the wire, neither candidate will want to lose ground on the closing straight.

It will take some expert political cunning, however, to determine when and how to dart back out on the campaign trail full time without appearing callous or insensitive to the plight of storm victims.

Stumping for votes in Virginia when more than 170,000 customers are without power would hardly appear to be a winning strategy, and yet the state is one of the nation's top three political battlegrounds, along with Florida and Ohio.

On Sunday, Obama advisor David Axelrod had worried publicly that the storm would dampen turnout in the early voting so vital to the president's hopes in states like Virginia.

“Obviously we want unfettered access to the polls because we believe that the more people come out, the better we're going to do,” a blunt Axelrod said.

Historically, a large election turnout has generally favoured Democrats.

But trouble looms for conservatives in Virginia's rural southwest, where residents were in for a major snowstorm that could keep many in the largely Republican region away from the polls.

Another place the storm could directly affect the vote is Philadelphia, the Democratic bastion in left-leaning Pennsylvania. Nearly 400,000 people were without power in and around the city Monday night.

Democrats need Philadelphians to vote in large numbers; if they stay home it presents an opportunity for Romney to snatch a vital state.

The storm also offered opportunity, albeit on a political knife-edge, for Obama, allowing him to pose as a cool, effective leader, marshaling government resources at a moment when citizens most need them.

Should the federal response fall short, it could revive bitter memories of Hurricane Katrina in 2005 and leave some undecided voters feeling like they would prefer change in the White House.

Former president George W. Bush was widely seen as having bungled the handling of Katrina, which devastated New Orleans. The failure of authorities in the ensuing emergency response tainted the rest of his presidency.

Sandy also posed peril for Romney – not just as Obama pulls the levers of incumbency, but as it threatened to drown out his closing arguments ahead of the November 6 election, with days of storm-dominated news coverage.

Romney canceled campaign events in Virginia but he kept a date Monday in each of two toss-up states, Ohio and Iowa.

He holds another event Tuesday in Ohio, perhaps the key battleground of the election, but has shifted it to a “storm relief event” which would present him with an opportunity to show leadership from outside of Washington.