GOP presidential hopeful Mitt Romney and his newly tapped running mate will head to different parts of the country today as they campaign to win over voters in the race for the White House. NBC's Peter Alexander reports.

ST. AUGUSTINE, Fla. -- Mitt Romney returned to the campaign trail in this critical swing state Monday morning without his new running mate, but armed with new rhetoric accusing President Obama of running a dishonest campaign meant to deceive the American people.

"With a record, which has been as disappointing as the record that he’s demonstrated over the past four years, the president’s campaign has resorted to a very unusual tactic," Romney said. "It’s smear. It’s dirt. It’s distortion. It’s deception. it’s dishonesty. It diminishes the-- it diminishes the office of the presidency itself."

Justin Sullivan / Getty Images Republican presidential candidate Mitt Romney speaks during a campaign rally at Flagler College on Aug. 13 in St Augustine, Fla.

With those remarks, Romney may have been pre-butting Democratic attacks on his running mate, Congressman Paul Ryan of Wisconsin. Ryan's Medicare overhaul plan would turn Medicare into a voucher or "premium support" program for those that would qualify for Medicare in 10 years (those 55 and younger). The plan would cap the amount that can be spent, prompting critics to say it would likely shift the burden, or the rest of the cost, to seniors.

The Daily Rundown's Chuck Todd breaks out the decision app to see how Romney's choice for running-mate might do harm to the duo when it comes to gaining the senior citizen vote.

The plan has become a lightning rod on both sides of the aisle. Romney contrasted the Republican ticket's plan with what he claimed were $700 billion in cuts to Medicare as part of the president's healthcare reform act.

But as First Read wrote this morning: "What Obama did under the health care law was reduce the rate of growth in non-essential services (like Medicare Advantage), as well as increase premiums for higher-income recipients. That doesn't affect the Medicare benefits that current/future seniors receive."

"We want to make sure we preserve and protect Medicare," Romney claimed.

Romney supporters at the morning event here downplayed the negative effect a renewed focus on Medicare reform might have here in Florida, with its large voting block of senior citizens.

"It's going to change, but its not going to change drastically and nobody is going to be deprived," said retired lawyer Bill Graham, a Romney supporter. "Now, how that's coming about in Ryan's plan? At least he's got a plan. At least he's got something that can be laid out and looked at. "

This is going to be Democrats' challenge -- to convince people that what they're saying about the Ryan plan is actually true. But Democrats also have to be careful not to overplay their hand. On MSNBC's The Daily Rundown this morning, former White House Press Secretary Robert Gibbs claimed that his father, who's 83, would be getting a voucher.

Todd pointed out that's false. “Your father is not going to get that, because they’re not going to do anything to him" because the plan would not affect those older than 55.

Phebe Wehr, a retiree from St. Augustine, said Romney and Ryan needed to be much more specific in selling their plan to current seniors.

"People are out there saying on their placards, 'Don't take away my Medicare;' they won't be," Wehr said. "So, they have to make that a lot clearer. I think Ryan's programs are going to be misunderstood."

Romney also used some new language to pump up the energy level today, which was diminished from Sunday night's rallies in part by slow security lines which left hundreds of supporters on the sidewalk outside the metal detectors and single security checkpoint.

"I know there are people around the world who are always critical of America, have something negative to say, say our greatest days are in the past. Baloney," Romney said. "We just won more Olympic medals than any other nation on Earth. We also just, we just landed on Mars and took a good look at what's going on there. And I know the Chinese are planning on going to the moon, and I hope they have a good experience doing that, and I hope they stop in and take a look at our flag that was put there 43 years ago!"

Romney has been critical of President Obama on space. At an NBC debate in Tampa during the GOP primary he said space should be a "priority." But he didn't specify how much he would spend, whether he would increase or decrease NASA's budget, but instead called for a "collaborative" effort between government, commercial enterprise, and universities.

At another debate, Romney mocked Newt Gingrich's moon colony idea, but also lamented the idea of candidates going state to state with big promises.

"The Speaker comes here to Florida, wants to spend untold amount of money having a colony on the moon," Romney said. "I know it's very exciting on the Space Coast. ... Look, this idea of going state to state and promising what people want to hear, promising billions, hundreds of billions of dollars to make people happy, that's what got us into the trouble we're in now. We've got to say no to this kind of spending."

Also part of the program today -- Florida's junior Sen. Marco Rubio, whom Romney admitted was vetted for the vice-presidential slot, but was passed over in favor of Ryan, a decision about which some Floridians were circumspect.

"I thought if he wanted to win he should have picked Marco Rubio," said Paul Merana, 70, a retired military officer. "But Paul Ryan is a good second choice."