JACKSONVILLE, Fla. (AP) ? Campaigning in coveted Florida, President Barack Obama warned Thursday that Republican challenger Mitt Romney would be "squeezing more money out of seniors" by turning Medicare into a voucher program. Romney, firing away near his Boston home base, accused Obama of putting his needs above those of the nation.
The daily war of words came as polling shows the presidential contest continues to be close nationally, with both men pouring most money and attention in into the collection of less than 10 states expected to decide the election. First lady Michelle Obama launched a new effort to rally supporters behind her husband, trying to light a fire by saying the whole race could "come down to just a few votes per precinct in key states."
The president opened two days of campaigning in Florida in search of military veterans, seniors and unaligned voters in the state's crucial midsection. Florida is the largest and most coveted of the nation's Election Day toss-up states, a place where Romney could severely damage Obama's chances of winning re-election.
In Jacksonville, the president broadened his attack on Romney's support for a House Republican plan that would change Medicare from a fee-for-service program into one where future retirees buy insurance using government subsidies. Republicans argue it would introduce competition and give seniors more choices.
"He plans to turn Medicare into a voucher program," Obama said. "So if that voucher isn't worth enough to buy the health insurance that's on the market, you're out of luck. You're on your own. ... We shouldn't be squeezing more money out of seniors who are just barely getting by right now."
Obama was later expected to make that pitch to seniors in West Palm Beach, where he'll visit Century Village, a condominium complex that's home to thousands of retirees, long a bastion of reliable Democratic voters.
Romney, in hastily arranged remarks to reporters near Boston, kept the focus on the sluggish economic recovery under Obama's watch. He cited new government figures showing that the number of American seeking unemployment benefits rose by 34,000 last week, a figure that may have been skewed higher by seasonal factors.
For a second day, he also mocked Obama for not having met with his advisory jobs council in six months while holding more than 100 fundraisers in that time. White House spokesman Jay Carney had said Wednesday that the president gets advice from the council all the time but also has "got a lot on his plate."
"I think you've learned something about the president's priorities," Romney said. "The job he's interested in protecting is his own."
The White House sought to counter the line of attack by showing presidential action. Obama's administration announced it was speeding up expansion projects at five major U.S. ports, including two in politically important Florida, just as Obama was flying there to rally votes and raise money during stops in Jacksonville and West Palm Beach.
Carney made a point to note that the idea came from Obama's jobs council.
As Obama stuck to his economic message, his campaign kept up its aggressive attempt to raise doubts about Romney's trustworthiness. Obama and his surrogates have been pushing Romney to release more than two years of tax returns. Some members of Romney's party have agreed, although others say the idea is a distraction.
"We've given all you people need to know and understand about our financial situation and about how we live our life," Romney's wife, Ann, told ABC News in an interview broadcast Thursday.
In a separate interview aired Thursday on WTOL-TV in Toledo, Ohio, Romney said one reason not to release more of his returns was that "the Democratic Party and the opposition has all these people that comb through and try and find anything they can to distract from the issues people care about, oftentimes in a dishonest way."
Romney had planned a quiet day of private meetings Thursday at his campaign headquarters in Boston, but abruptly changed his plans and scheduled his campaign stop nearby to coincide with Obama's first event in Florida.
Republicans are holding their national convention in Tampa in August in hopes of giving themselves an edge in the state.
Yet, if Obama can lock down Florida's 29 electoral votes, it would be difficult for Romney to mount enough support elsewhere to capture the White House.
Polls have shown Obama and Romney in a dead heat in the state, which has struggled with an unemployment rate of 8.6 percent, above the national average, and a still-recovering housing market. Florida provided the deciding margin in George W. Bush's victory in 2000 and the state has been closely contested ever since. Obama carried it in 2008.
Romney, under attack for days over his record running the Bain Capital private equity firm and over his tax returns, went on the offensive this week and lashed out at Obama for saying: "If you've got a business, you didn't build that. Somebody else made that happen." He did so again Thursday.
The Obama campaign says the president's comment has been distorted, and that the full context shows that he was underscoring the important role government plays in helping people prepare for success based on their individual initiative.
Peoples reported from Roxbury, Mass. AP White House Correspondent Ben Feller and Associated Press writers Jim Kuhnhenn and Mark S. Smith in Washington contributed to this report.