WASHINGTON - One day out from their last debate, Republican Mitt Romney and President Barack Obama are cramming foreign policy and taking a rare break from swing-state campaigning. Monday's face-off in Boca Raton, Fla., represents one of the last major opportunities for Obama and Romney to capture the attention of millions of voters -- especially that small but sought-after group of voters who haven't yet made up their minds. Obama was holed up in Camp David in Maryland's Catoctin Mountains, where he arrived Friday to prep for the debate, a 90-minute encounter focused on international affairs. With him at the presidential retreat were a band of top advisers including National Security Adviser Tom Donilon, campaign strategist David Axelrod and White House senior adviser David Plouffe. Romney planned to spend the weekend in Florida, continuing intensive preparation that has consumed large amounts of his time in recent weeks. Foreign policy has surfaced as a prominent issue in the waning weeks of the race, elevated by a deadly attack on the U.S. Consulate in Benghazi, Libya, and a restive situation in Syria. Although polls show voters continue to prioritize economic issues, both candidates are aggressively pitching themselves as more competent to be commander in chief. In an unusually quiet day on the campaign trail, Romney running mate Paul Ryan was the only candidate to be out in front of voters. The Wisconsin congressman plans two events Sunday in Iowa, including one in Sioux City with country singer Mark Wills, plus an evening rally in Colorado. Still, with a tight race closing in, neither Romney nor Obama can afford more than a few days away from the handful of states that will decide the winner. Obama planned a whirlwind excursion starting after Monday's debate. Events Tuesday in Florida and Ohio will be followed by around-the-clock campaigning Wednesday in Davenport, Iowa; Denver; Los Angeles and Las Vegas. Then on to Tampa, Fla.; Richmond, Va.; and Cleveland on Thursday, when Obama will also return home to Chicago to vote early as part of the campaign's push for early and absentee voting. In a sign that the candidates' time has become the most precious commodity, Obama's aides said he planned to sleep Wednesday night aboard Air Force One and would call undecided voters from the airplane between stops.