Mitt Romney jumpstarted his White House campaign on Wednesday after a pause for deadly storm Sandy, but an aide said the Republican had no plans yet to see storm damage or victims ahead of next week's election.

With just six days before US voters go to the polls, the Romney campaign has begun to map out its final strategy to defeat President Barack Obama, hitting several of the biggest swing states on the last days of the race.

He heads to Virginia on Thursday, then Wisconsin and the crucial battleground of Ohio, where he will be joined by his running mate Paul Ryan on Friday.

And on Monday, Romney holds his final "victory rally" of his campaign, in the small toss-up state of New Hampshire, where he has a second home.

Romney laid low on Tuesday, cancelling campaign events, as Obama wielded the vast powers of incumbency from Washington to oversee emergency operations and crisis response during the storm that has killed dozens and paralyzed several cities including New York.

The Republican nominee charged out of the gate in sunny Florida on Wednesday, seeking to muscle into the political conversation that has been swamped by superstorm Sandy.

But even as attention focused on the devastation that has hit the US East Coast, and Obama toured stricken New Jersey with Republican governor Chris Christie, senior aide Kevin Madden said Romney had no plans as of Wednesday to visit communities or victims battered by Sandy.

"I don't have any updates on anything about travel with storm damage," Madden said on the Romney campaign plane. "I don't have any plans that I can confirm beyond what we have on Thursday right now, for travel."

The comments raise the possibility that Romney will have no engagement with the regions hardest hit by Sandy in the run-up to the election, other than making weekend calls to Christie and fellow Republican governors Bob McDonnell of Virginia and Pennsylvania's Tom Corbett.

Asked what Romney's reaction has been to Obama's handling of the storm relief operations, Madden pointed instead to remarks by Christie, who offered effusive praise for the commander-in-chief.

"I refer you to Governor Christie's remarks. I believe the response is still going on, so I'm not in a position to qualify the response by the federal government," Madden said.

Christie made headlines at the weekend when he praised the president's "wonderful" handling of the crisis and his engagement with the Republican governor, whose state, particularly coastline communities like Atlantic City, was devastated by the storm.

But with the election on November 6, and the race a dead heat, the Republican nominee can ill afford another day off the trail.

He leads in some national polls, and holds the narrowest of leads in the biggest battleground of all, Florida. But many surveys show Obama maintaining a slight edge in most toss-up states like Ohio and Iowa.

Unable to match Obama's presidential imagery as commander in a crisis, Romney enlisted some political backup in the form of Senator Marco Rubio and popular former Florida governor Jeb Bush.

Despite hitting the trail with his standard pledge to turn around the ailing economy, Romney addressed the plight of storm-battered Americans who have been "subjected to this tragedy."

"So please, if you have an extra dollar or two, please, send them along and keep the people who have been in harm's way... in your thoughts and prayers," he told about 2,000 people in an airport hangar in Tampa, as American Red Cross donation messages flashed on large video screens.

While Romney rapidly shifted to his message that "it's time for America to take a different course," the challenger held off on direct attacks against Obama, instead pushing optimism and the bipartisan cooperation needed to meet US fiscal challenges.

He said that would take "something that Washington talks about but hasn't done in a really long time, and that is truly reaching across the aisle and finding good Democrats and good Republicans" to enact reforms.

At a rally in a university arena outside Miami, Romney said he'd embark on "a new path of bold, aggressive change" if elected, "because the one we're on is not doing so well."

Florida is the largest of several battlegrounds Romney must win if he is to bounce Obama out of the White House.

"America is counting on Florida. I'm counting on Florida," Romney said.