TAMPA, Florida (AFP) — Mitt Romney renewed his White House campaign yesterday with a trio of rallies in Florida, after President Barack Obama grabbed headlines by commanding the federal response to superstorm Sandy.

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

But with just six days until the November 6 election, 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, Iowa and Colorado.

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, who introduced Romney.

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, as American Red Cross donation messages flashed on large video screens.

"We come together in times like this, and we want to make sure they have a speedy and quick recovery from their financial and, in many cases personal, loss," Romney added.

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 as the president presided over storm duties in Washington.

Instead, he stressed the need for bipartisan action to tackle monumental challenges like fiscal impasses, tax reform, expansion of energy production and improvement of conditions for small businesses — all parts of his political platform.

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.

"I don't just talk about change. I actually have a plan to execute change and to make it happen," he said.

Romney has two more rallies in Florida, then heads to battlegrounds Virginia on today and Ohio on Friday.