While Obama and Romney moved cautiously Tuesday, their campaigns exchanged sharp words in Ohio and expanded their operations into three Democratic-leaning states, a move that will reshape the contest's final six days.
Romney's campaign is running ads in Minnesota and Pennsylvania, and a pro-Romney group is doing the same in Michigan. Obama was leading in all three, but his campaign is taking the threat seriously. It sent former President Bill Clinton to Minnesota on Tuesday and it is buying airtime in all three states, although senior Obama adviser David Axelrod flatly said they are safe.
"I will shave off my mustache of 40 years if we lose any of those three states," Axelrod said in an appearance on MSNBC's "Morning Joe."
Republican strategists differ on the Romney campaign's thinking. Some think Romney's aides fear losing all-important Ohio, and they hope for a stunning last-minute breakthrough elsewhere to compensate. Others say the GOP camp has so much money - and so few chances to buy useful airtime in saturated states - that it can spend millions of dollars on a long shot without scrimping in a battleground.
"If they didn't have so much money, they wouldn't be able to do something with so little chance of success," said Democratic strategist Tad Devine.
Another sign that Ohio looms large for the Romney campaign: a guest-filled rally in suburban Cincinnati on Friday to kick off the campaign's final four days. Set to join the GOP ticket are golf legend Jack Nicklaus, former Secretary of State Condoleezza Rice, Texas Gov. Rick Perry and former New York City Mayor Rudy Giuliani.
Meanwhile, Democratic groups bitterly complained about a TV ad the Romney camp is running in the Toledo and Youngstown areas of Ohio. The ad suggests that Jeep will move its Toledo car-making facility to China, a claim Jeep executives deny.
Democrats called the ad a brazen lie and a sign of desperation. Even some Republicans worried that Romney has gone too far in a state where voters follow the auto industry closely.