Heading into the campaign’s final weeks, Republican presidential candidate Mitt Romney is upping his criticism of President Barack Obama’s plans for a second term, accusing the Democrat of failing to tell Americans what he would do with four more years. The Obama campaign is aggressively disputing the notion, claiming it’s Romney who hasn’t provided specific details to voters.

At campaign events, in a new ad and fundraising appeal out Saturday, Romney is setting up the closing weeks as a choice between what he says is a “small” campaign that’s offering little new policy and his own ambitious plan to fundamentally change America’s tax code and entitlement programs.

The new Romney ad criticizes the president’s policies on debt, health care, taxes, energy and Medicare, arguing that Obama is simply offering more of the same. The campaign did not say where the spot would air. The fundraising appeal hits Obama for raising taxes and increasing the debt by $5.5 trillion, repeating the lack-of-agenda criticism.

“Although President Obama won’t lay out his plan for a second term, we already know what it will be — a repeat of the last four years. We can’t afford four more years of crushing debt and wasteful spending,” Romney says in the letter, adding he has a clear plan to put America on a path to prosperity.

Both Obama and Romney retreated from the campaign trail Saturday to bone up on foreign policy, leaving the work of courting voters to their running mates.

Vice presidential candidate Paul Ryan on Saturday continued the no-agenda theme against Obama at campaign stops near Pittsburgh and in Belmont, Ohio.

“He’s not even telling you what he plans on doing,” Ryan told a rain-soaked crowd of about 1,100 people at a campground in coal-rich eastern Ohio.

Obama’s campaign disputes the notion that the president hasn’t outlined a detailed second-term agenda, pointing to his calls for immigration reform, ending tax breaks for upper income earners, fully implementing his health care overhaul and ending the war in Afghanistan.

In a statement sent after Romney’s Friday night event, Obama campaign spokesman Danny Kanner ticked through a series of policy items, calling them “just part of President Obama’s agenda for a second term.”

Obama, at the Democratic National Convention, called for creating 1 million manufacturing jobs over the next four years with a mix of corporate tax rate cuts and innovation and training programs. He has set a goal of cutting the growth of college tuition in half over the next 10 years. He also has called for Congress to pass proposals he made last year that include includes tax credits for companies that hire new workers and funding for local municipalities to hire more teachers, police officers and firefighters.

As for why Republicans would back the same proposals they have already voted against, Obama has told supporters he expects his re-election would “break the fever” on Capitol Hill that led to gridlock during his first term.

Vice President Joe Biden made a diagnosis of his own on Saturday, saying Ryan had caught “Romnesia,” the word Obama used the day before to describe what he calls Romney’s changing polices.

“That man is contagious,” Biden said of Romney, to loud cheers at a campaign stop in St. Augustine, Fla. “Congressman Ryan caught it as well.”

He said the Wisconsin Congressman is now giving a new explanation for cuts in the budget he oversaw and passed in the House.

The president’s aides are particularly irked by the questions about Obama’s second-term agenda, because they say it’s Romney who has failed to provide voters with details. They point to his refusal to provide specifics about his tax plan or outline what he would replace the president’s health care overhaul with if he makes good on his promise to repeal the federal law.

An independent group backing Obama, though, is trying to renew attention on Romney’s tenure at the helm of the private equity firm Bain Capital. The group, Priorities USA Action, is re-airing an ad about an AMPAD plant in Marion, Ind. That spot features former employee Mike Earnest recalling being told to build a stage from which officials of the office supply company later announced mass layoffs.

He says, “It was like building my own coffin.” That ad first aired in battleground states in the summer.

Romney aides have said AMPAD was a struggling business to begin with, and Bain overall created many more jobs than were lost.

That ad will air in Colorado, Florida, Iowa, Ohio, Nevada, Virginia and Wisconsin. The new campaign will be in addition to a $30 million effort against Romney policy proposals, the group said.

Monday’s debate in Boca Raton, Fla., with its focus on international affairs, is the third and final between the two rivals and comes just 15 days before the election.

Obama left Friday for Camp David, the presidential hideaway in Maryland’s Catoctin Mountains, where he is huddled with advisers preparing for the debate. Among those with him are White House senior adviser David Plouffe and senior campaign strategist David Axelrod. Aides say Obama was also being assisted by National Security Adviser Tom Donilon and former Obama aide Karen Dunn.

Romney was also with aides preparing for the debate, spending the weekend in Florida.

Both campaigns are heavily targeting Florida and its 29 electoral votes — the most of any tossup state. It was the second day of a two-day Florida swing for Biden, which overlapped a two-day swing by Ryan. Romney’s wife, Ann, was also in Florida Saturday and First Lady Michelle Obama planned a visit Monday, ahead of the presidential debate that night in Boca Raton. The president is planning at least two days of campaigning in Florida after the debate.

Monday’s 90-minute debate will be moderated by Bob Schieffer of CBS News. It will be similar to the first debate, with both men standing at lecterns on a stage. Schieffer has listed five subject areas, with more time devoted to the Middle East and terrorism than any other topic.

While the economy has been the dominant theme of the election, foreign policy has attracted renewed media attention in the aftermath of the attack on the U.S. Consulate in Benghazi, Libya, that killed four Americans, including U.S. Ambassador Chris Stevens.

Obama had ranked well with the public on his handling of international issues and in fighting terrorism, especially following the death of Osama bin Laden. But the administration’s response to the Libya attack and questions over levels of security at the consulate have given Romney and his Republican allies an issue with which to raise doubts about Obama’s foreign policy leadership.

Romney has spent large amounts of time off the campaign trail to prepare for the upcoming foreign policy debate. Aides say the additional time preparing is well-spent even if it comes at the expense of public events.

(AP)