President Barack Obama has no clear plan for the next four years, Republican vice presidential candidate Paul Ryan said Thursday.

Ryan spoke for about an hour to an enthusiastic crowd of several thousand in Ocala, Fla., and took questions on topics ranging from Social Security to homeschooling.

But Ryan's primary target was the president, and he drew distinctions between Obama and his running mate, Mitt Romney.

"We have a moral obligation to save the American dream," Ryan said. "We have a very clear choice: stagnation or growth."

Ryan spoke at length about Social Security and Medicare, saying that for people 55 and over, the programs wouldn't change under the GOP ticket's plan. For younger generations, Ryan said he advocates subsidies -- with amounts yet to be determined -- to help future retirees buy private insurance or join a government plan modeled on traditional Medicare. He said the Republican plan would give people more choice.

Ryan also charged the Democratic incumbent with sending a divisive message.

"He's basically trying to disqualify his opponent with a sea of negativity," Ryan said. "He's trying to divide this country, pitting people against each other. He's trying to win this election by default. You know what, we're not going to let him get away with that."

Ryan took a handful of questions from the crowd, including one on homeschooling.

"We believe in freedom. If you believe the best way to raise your children is to homeschool your children, then God bless you," Ryan said.

The crowd, comprised of many retirees, appeared to enjoy Ryan's remarks.

"I think he's a good speaker, I like him," said 66-year-old Charles Alstrin, a retired mechanical engineer. "I agree with most of what they are saying."

Alstrin said his mind has been made up for months about voting for Romney, and said he appreciated Ryan's frequent use of numbers and statistics to bolster the campaign's assertions.

"I think there needs to be more numbers," said Alstrin. "How much does this debt cost us individually? I would like to hear most of these numbers in individual terms, or in unit terms, like a family."

In a news release sent minutes after Ryan left the stage, the Obama campaign asserted that Romney's plan will do the country more harm in the short term.

A few dozen Obama supporters stood on a nearby sidewalk and loudly booed and chanted during Ryan's speech. One woman wandered the perimeter with a sign that read, "Mitt and Ryan are liars." It drew scorn from some GOP supporters.

"You don't know what you're talking about!" a man shouted at the woman with the sign.

Later Thursday, Ryan was scheduled to stop in Naples for a fundraiser and in Fort Myers at a campaign rally. On Friday, Ryan and Romney will appear at an event in Daytona Beach.

Democratic vice presidential candidate Joe Biden will make campaign stops in Florida on Friday and Saturday.