PORT ST. LUCIE, Fla. - Wrapping up his weekend-long swing in the battleground state of Florida, Republican presidential nominee Mitt Romney was greeted by one of his largest crowds to date, as the groups of supporters coming to see him speak having grown daily since the debate.

Romney drew an estimated crowd of 5,600 on Friday in St. Petersburg, another 6,300 in Apopka on Saturday night, and here today just outside Palm Beach, it was estimated that more than 9,000 came to Romney's event. While these crowds are still significantly smaller than those of President Obama - who drew an estimated 30,000 people one day last week in Wisconsin - the campaign has reported that the support Romney has enjoyed since the debate is evident also in fundraising, raising $12 million in online donations in the 48 hours after the debate alone.

Here today, Romney bounded on stage beside his wife Ann, greeted the crowd who had waited through soaring temperatures and then later rain, and told the crowd, "This is an extraordinary sight gathered here today!"

"We're going to win Florida, we're going to take back the White House!" he said, the crowd erupting in applause.

Romney, still looking to ride the wave of goodwill his debate performance bought him among his critics, offered his own assessment of Obama's performance.

"You all had the chance to hear his answers or his non-answers, now of course days later we're hearing his excuses and next January we'll be watching him leave the White House for the last time," Romney said.

After debuting a series of personal stories on Friday evening, an attempt by him and his campaign to show a more compassionate side, Romney did so again here tonight.

"It may be a little cloudy today but the sunshine is coming through, guys, in this country," Romney said, giving a nod to the ever-changing weather conditions in Florida.

"I've had the occasion throughout my life to see something about the great qualities of the human spirit exhibited in the American people time and time again, I know something about great human beings in this country," he said. "It's that that gives me the confidence that our future will be so bright because I've seen how Americans respond to challenge and even to tragedy."

Romney heads this evening to another must-win battleground state, Virginia, where he will hold several campaign events on Monday, including a major foreign policy speech.