After a warm welcome at a rally in Fairfax, Va., Romney, 65, told cheering supporters: "I'm looking around to see if we have the Beatles here or something to have brought you. But it looks like you came just for the campaign and I appreciate it."
Wife Ann Romney addressed the crowd in suburban Washington, too.
"Are we going to be neighbors soon?" she asked hopefully.
Ryan alone logged more than 2,500 miles Monday as he hopped from Nevada to Colorado to Iowa to Ohio to Wisconsin.
At a rally in Reno, Nev., he told voters: "This feels like deja vu, doesn't it? You've seen a few of us around, haven't you?" He'd been at a rally just around the corner on Thursday.
Vice President Joe Biden crisscrossed Virginia, and fondly recalled his debate with Ryan during a stop in Richmond.
"You all learned what 'malarkey' means, didn't you?" he said. "Well, I heard a lot of malarkey."
Just in case everyone wasn't paying attention, Obama and Romney made a play for those tuned in to "Monday Night Football," each making satellite appearances on ESPN that aired during halftime of the Philadelphia Eagles-New Orleans Saints game.
The forecast for Election Day promised dry weather for much of the country, with rain expected in two battlegrounds, Florida and Wisconsin. But the closing days of the campaign played out against ongoing recovery efforts after Superstorm Sandy. Election officials in New York and New Jersey were scrambling to marshal generators, move voting locations, shuttle storm victims to polling places and take other steps to ensure everyone who wanted to vote could do so.
Obama, who voted 12 days early, was sure to observe his Election Day ritual of playing pickup basketball with friends and close advisers. The one time he skipped the tradition, he lost the New Hampshire primary in 2008.