Obama told an audience in Cincinnati Romney is "a very talented salesman" who "has tried as hard as he can to repackage the old ideas that didn't work as new ideas."
"In fact, he's offered them up as change -- says he's the candidate of change," Obama said. "Now, here's the thing, Cincinnati. It turns out we know what change looks like. And what Governor Romney is selling is not change. Giving more power back to the biggest banks -- that's not change. Another $5 trillion tax cut that favors the wealthy -- not change. Refusing to answer questions about the details of your policy until after the election -- definitely not change. That's the oldest trick in the book. Ruling out compromise by pledging to rubber-stamp the Tea Party's agenda in Congress -- not change. Changing the facts when they're inconvenient to your campaign -- not change."
Romney told a crowd in Cleveland there is a possibility Obama could be re-elected, but he didn't think it likely.
To shouts of "No!" and laughter from the audience, the Huffington Post quoted the Republican presidential nominee as saying, "If the president were to be re-elected -- it's possible, but not likely -- If he were to be re-elected, he will still be unable to work with people in Congress, because he's ignored them, he's attacked them, he's blamed them."
Romney and Obama are fighting fiercely for Ohio's 20 electoral votes only two days before the election.
Earlier in the day at McArthur High School in Hollywood, Fla., Obama told supporters they faced "a choice between two different visions of America."
"On the one hand," he said, "you can choose the return to the top-down policies that crashed our economy -- or you can join me in building a future that focuses on a strong and growing middle class."
Obama hearkened back to Bill Clinton's eight years as president, noting 23 million jobs were created during his tenure and the federal government wound up running surpluses instead of deficits.
"But a Republican candidate by the name of Mitt Romney said Bill Clinton's plans would hurt the economy and kill jobs. Turns out his math was just as bad back then as it is now," Obama said.
"So, Florida, we know that our ideas work. We also know that their ideas don't -- because we tried their ideas, too. We tried giving big tax cuts to the wealthiest Americans. We tried giving insurance companies and oil companies and Wall Street free rein to do whatever they pleased. And you know what we got? We got falling incomes and record deficits and the slowest job growth in half a century and an economic crisis we've been cleaning up after ever since."
Early voting in Florida's Miami-Dade County was extended to Sunday to allow voters to request and cast absentee ballots in person, The Miami Herald reported.
The decision was announced Sunday morning after the Florida Democratic Party sued in Miami federal court over a loophole in a state law that eliminated early voting the Sunday.
Meanwhile, with a few days left before the U.S. presidential election, both candidates encouraged supporters to go into their communities and convince others to vote.
The race is so tight, Romney told voters Saturday in New Hampshire to visit the homes of people who have Obama signs in their yard to try to change their minds, Politico reported.
Obama also told New Hampshire voters to make sure their friends and neighbors head to the polls Tuesday.
"Make sure they vote for me before you drag them to the polls," he added.
The latest batch of polls show Obama leading Romney in the battleground states of Ohio and Iowa, but a mixed picture in Florida. An NBC News/Wall Street Journal/Marist poll showed Obama leading Romney 51 percent to 45 percent in Ohio, and 49 percent to 47 percent in Florida.
A Columbus Dispatch poll released Sunday shows Obama holds a slimmer lead over Romney, at 50 percent to 48 percent, The Hill reported.
Meanwhile, a Miami Herald/El Nuevo Herald poll has Romney ahead of Obama at 51 percent to 45 percent.
The Des Moines Register poll released Saturday shows the president up 47 percent to 42 percent.