JACKSONVILLE, Fla. -- About 12,000 supporters -- some who had waited for hours under overcast skies -- cheered when Sen. Barack Obama appeared at a "Change We Need" rally at Metropolitan Park Saturday afternoon. Up to 8,000 others were turned away when police said the park reached capacity about one hour before the program began.

The Democratic presidential nominee took the stage just over an hour later, saying, "What an unbelievable crowd."

"Are there any Gator fans in the house? It sounds like there might be some Bulldogs out here. I guess there's one Seminole out here," Obama said. "I'm amazed we got such a big crowd. I don't know if ya'll are aware, there's football today."

Once the crowd settled, Obama turned serious, acknowledging the bombing in Pakistan that took many lives Saturday morning.

"I addition to the threat abroad, I think everyone here understands that we've gone through some very difficult times here at home," Obama said. "The events of this week have shown that the stakes of this election could not be higher; they could not be clearer. We are in the midst of the most serious financial crisis in generations."

The Illinois senator said this does not come as news to the people in Jacksonville, who are dealing with rising unemployment and rising prices. He talked about his plan to "steer ourselves out of this crisis."

Then he turned his attention to his opponent, "because he's been talking about me."

"President Abraham Lincoln -- from my home state of Illinois -- he once had a comment that applies here. He said to one his opponents, 'If you don't stop lying about my record, I'm going to have to start telling the truth about yours.'"

The partisan crowd began chanting, "Obama, Obama."

"Don't believe what those people say," Obama told the audience. "I will cut taxes for 95 percent of all working families. If you make less than a quarter million dollars a year -- is that you? -- you will not see your taxes increase one dime."

He argued that McCain has no solutions for the nation's eocnomic crisis.

"I am running for president because we can't afford four more years of a do-nothing economic philosophy that works for Wall Street instead of Main Street, and ends up devastating both," Obama said. "This election is a chance to stand up and say, 'Enough is enough.'"

Then he turned specifically to why he spend Friday and Saturday in the state.

"Florida, I need you to make it happen.... I can't win this alone," Obama said. "If you're not behind me, if you don't feel that fierce sense of urgency -- what Dr. King called the urgency of now -- then we may not cross that finish line."

The Democratic nominee made a promise that if the people of the state support his campaign, "we will not just win Florida, we will win this general election, and you and I together will change this country and change the world."

The campaign had warned that space in Metropolitan Park was limited and available on a first-come, first-served basis. Tickets were not required for the event, but many who went online to RSVP were among those left outside. So were some dignitaries, media and even Obama staff members.

Some who could not get in to see the nominee were frustrated, even angry, chanting, "Open the gate."

"They should have held it at the stadium," one woman said.

"I'm frustrated that I can't get in, but I'm thrilled at the turnout," another supporter said.

Obama's Jacksonville stop followed a women's rally at the University of Miami on Friday and a similar event Saturday morning at Bethune-Cookman University in Daytona Beach.

Obama is trying to court Florida voters at a time when polls shows the race between the Illinois senator and Republican candidate Sen. John McCain tightening. Florida again is expected to be one of the key battleground states, with 27 electoral votes up for grabs.

McCain made stops in the state's four largest cities, starting with a rally at the Veterans Memorial Arena on Monday.

McCain's running mate, Gov. Sarah Palin, will make her first campaign to visit to Florida on Sunday. The Alaska governor will hold a rally at The Villages, a large retirement community one hour north of Orlando.

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