"We don't envision a circumstance in which the Democratic National Convention doesn't seat delegates from Michigan and Florida," Clinton campaign Communications Director Howard Wolfson said on a conference call with reporters Tuesday afternoon, reports ABC News' Eloise Harper. "We know at the end of the day these delegations are going to get seated."
McCain's win has also taken the wind out of Romney's sails, although Romney remains in the stronger financial position and is able to fund costly television ads in Super Tuesday states.
Romney, who has already spent $17 million of his own fortune on his White House bid as of Sept. 30, made a joke during his concession speech about it.
He told the crowd they all felt like family, but "don't expect to be part of the inheritance … not sure there is gonna be much left after this."
A Romney campaign aide told ABC News' John Berman that McCain's win in Florida is due, in part, to "McCain's superior name ID" but emphasized that now there is a two-man race going into Super Tuesday.
In recent days, McCain also won key endorsements by Florida Sen. Mel Martinez and Florida's Republican Gov. Charlie Crist.
"We were on track to win after the debate and McCain knew it," a Romney adviser told Berman. "Martinez and Crist changed [the] dynamic."
The Romney aide also says McCain's negative campaign tone this weekend took a toll. McCain "got dirty at the end," said the Romney adviser. "He got negative and nasty."
McCain and Romney have waged an acrimonious battle against each other for the Sunshine State, with Romney painting McCain as a Washington insider with liberal Democratic policies, and McCain describing Romney as a serial flip-flopper who has moved to the right on multiple issues since announcing his presidential bid.
McCain's claim Saturday that Romney supported Democratic plans for a specific date for troop withdrawals from Iraq threw Romney off his message, Berman reports. He seemed angry, and ended up playing for a day in McCain's "wheelhouse."
Exit polls suggest veterans turned out in large numbers, which may have benefited McCain, who touted his credentials as a veteran and a war hero.
Going into next Tuesday's multistate contest, McCain now has 95 delegates; Romney, 59; and Huckabee, 40. A candidate needs 1,191 delegates to win the GOP nomination. The Arizona senator also has bragging rights for having won the largest and most diverse state to vote so far. The momentum will be critical going into Feb. 5, when more than 20 states will vote, including California, which has 370 delegates up for grabs.
"The winner comes to California on a rocket ship," said Dan Schnur, a California-based Republican analyst who is unaffiliated with any campaign but worked as McCain's communications director during the 2000 primary.
All the leading Republican candidates are scheduled to appear at a Republican debate in California Wednesday night, including Giuliani, whose campaign status appears uncertain.
Earlier this week, McCain and Romney repeatedly blasted one another. Romney said McCain would set the nation on a "liberal Democratic course," while McCain said Romney's campaign is based on the "wholesale deception of voters."
At a polling station in St. Petersburg, Fla., this morning, McCain took some last digs at Romney when asked about the rising level of vitriol between the rivals.