To continue getting breaking news and the full stories from The Boston Globe, subscribe today.

The Boston Globe

Nation

Political notebook

In Florida, Obama puts Medicare at top of voters’ concerns

President Barack Obama high-fives Saint Christopher Sykes, 6, at a rally at St. Petersburg College's Seminole Campus on Saturday, Sept. 8, 2012 in St Petersburg, Fla.

AP Photo/The Tampa Bay Times, Will Vragovic, Pool

President Obama high-fived Saint Christopher Sykes, 6, at a rally at St. Petersburg College's Seminole Campus on Saturday, Sept. 8, 2012 in St Petersburg, Fla. (AP Photo/The Tampa Bay Times, Will Vragovic, Pool)

SEMINOLE, Fla. — President Obama began hammering away on Saturday at the Republican ticket’s plans for Medicare, using a campaign swing through Florida, with its large number of retired and elderly voters, to try to turn the page from anemic employment growth, his biggest weakness, to entitlements, a Democratic strength.

Kicking off a two-day bus tour through this perennial swing state, the president told a rally here that Mitt Romney’s running mate, Representative Paul Ryan of Wisconsin, has proposed to overhaul Medicare and replace it with a voucher system that could mean higher costs for beneficiaries.

‘‘Florida, you should know I will never turn Medicare into a voucher system,’’ Obama said, to rousing cheers from a crowd of 11,000 at St. Petersburg College, Seminole. ‘‘No American should have to spend their golden years at the mercy of insurance companies.’’

The president’s advisers have indicated that they are eager to reengage their opponents on their Medicare plan, while the Romney camp would prefer to talk about the economy. A government report on Friday showed that employers had eased up on hiring in August, adding just 96,000 jobs, compared with 141,000 in July. The unemployment rate dropped to 8.1 percent from 8.3 percent, but that was largely because of people leaving the workforce entirely.

Romney has sought to blunt Obama’s Medicare offensive with attacks of his own, something Obama advisers appeared to await eagerly.

‘‘If they want to have a discussion about who do you trust on Medicare for the next 60 days as their central argument, you know we ought to send them an in-kind contribution,’’ David Plouffe, Obama’s senior adviser, told reporters aboard Air Force One on Friday. ‘‘We’re happy to have that discussion. We think people trust the president more on Medicare.’’

Obama grabbed that mantle on Saturday and ran with it. ‘‘We will reform and strengthen Medicare,’’ he told the rally, ‘‘but we’ll do it by reducing the costs of health care, not by dumping the costs on seniors.’’

For good measure, he threw in several more lines in his stump speech aimed at seniors, who he said ‘‘are saving an average of $6,000 on prescription drugs because of Obamacare. And by the way, I do care.’’ It was a reference to the derogatory phrase that Republicans have given his health care overhaul. These days, the president has embraced the label.

‘‘I like the name ‘Obama­care,’ ’’ he said. Romney ‘‘says he’s going to repeal it. That’s because Romney doesn’t care.’’

After Seminole, the president traveled up Interstate 4 toward Orlando, with a stop in Kissimmee. On Sunday, he was to head down to Melbourne and then West Palm Beach, ground zero for the Bush-Gore recount of 2000.

Romney, a former Massachusetts governor, was focusing his efforts Saturday on Virginia, another state that Obama captured in 2008 and that he has made a priority in his reelection bid.

At his first stop, in Virginia Beach, Romney led the crowd in the Pledge of Allegiance, using it as a jumping-off point to criticize Obama and the Democrats for initially passing a convention platform that did not mention God.

‘‘The promises that were made in that pledge are promises I plan on keeping if I am president, and I’ve kept them so far in my life,’’ Romney told the cheering audience. ‘‘That pledge says ‘under God.’ I will not take ‘God’ out of the name of our platform. I will not take God off our coins, and I will not take God out of my heart.’’

The stop in Virginia Beach and an appearance at the start of the Sprint Cup Series ­NASCAR race in Richmond is intended to help him shore up his lead among white working-class voters.

Although the president trails Romney in this crucial demographic, some polls still show Romney underperforming among those voters. Romney’s choice of Ryan as his running mate was also expected to help him win over working-class whites and the Republican conservative base, many of whom remained wary of Romney during the early nominating contests.

For Romney, the son of a Detroit auto executive turned governor of Michigan, such courting of working-class voters may be a challenge. He is Harvard educated (both the business and law schools) and has an estimated net worth of more than $200 million.

During a visit to the Daytona 500 this year, Romney ran into some trouble when he said that while he did not follow the sport as closely as some ardent fans did, he had ‘‘some great friends who are NASCAR team owners.’’ His opponents used the comment to portray him as wealthy and out of touch with the concerns of average voters.

Obama has made repeated campaign stops in Virginia, particularly courting black voters around the Richmond area to try to drive up their turnout. He has also focused on liberal-leaning areas of Northern Virginia.

In addition to the on-the-ground campaigning this weekend, the Sunday morning talk shows were on the candidates’ agendas. Romney was to make his first appearance of the campaign season on ‘‘Meet the Press’’ on NBC, and Obama and Ryan were scheduled to appear on ‘‘Face the Nation’’ on CBS.