Republican presidential candidate Mitt Romney will be formally nominated in Florida on Tuesday (AP)
The Republican National Convention to nominate Mitt Romney as the party's challenger to President Barack Obama has been gavelled into session for just a few minutes in a largely empty hall, a symbolic opening as delegates waited out a tropical storm on course to bring back memories of Hurricane Katrina.
Republicans effectively cancelled the first day of an event aimed at repairing party unity after a bruising primary season and recharging the campaign before the November 6 election.
Polls show Mr Obama holding a small lead in a race dominated by concerns about the still-struggling economy.
Mr Romney's campaign looks forward to introducing their candidate to national TV viewers with high-profile speeches from him, running mate Paul Ryan and party leaders in an attempt to show Mr Romney as both a determined leader and a family figure.
They hope to counter Democrats' attempts to brand him as a ruthless titan of the business world.
But the convention's script was being hurriedly reshaped as Tropical Storm Isaac threatened to come ashore as a hurricane along the US Gulf Coast perhaps not far from New Orleans, almost seven years to the day after Katrina devastated the city, killed 1,800 and led to criticism of then-Republican president George W Bush's response.
Mr Romney suggested there were no thoughts of cancelling the convention and said he hopes those in the storm's path are "spared any major destruction".
The roll call of state delegations affirming Mr Romney as the party's nominee now is to unfold on Tuesday, an evening capped by speeches from wife Ann Romney and Republican governors.
Mr Ryan gets the prime-time spotlight on Wednesday, and Mr Romney will close the spectacle on Thursday night, his springboard into the final leg of the contest.