Both candidates argued they were the true agent of change, facing a rival who may talk a good game without the right policies to deliver.
"Candidate Obama promised change, but he couldn't deliver it," Romney charged. "I promise change, but I have a record of achieving it."
Obama retorted that Romney is "a very talented salesman," trying to repackage the old-school Republican policies that left so many Americans in financial trouble.
"We know what change looks like," Obama told an Ohio crowd. "And what the governor is offering ain't it."
Both candidates were plunging into a hectic pace of campaigning. Obama was eager to fend off Romney in the key battleground of Ohio even as Romney pushed to expand the contest to other states, most notably Pennsylvania, to secure the 270 electoral votes needed to win.
Obama directly took on Romney for the first time over the Republican's ads airing in Ohio on the auto industry bailout. The ads accuse Obama of taking General Motors and Chrysler into bankruptcy, selling Chrysler to an Italian company and building Jeeps in China. Chrysler and GM have protested the ads and disputed the suggestion that Jeep construction was being moved overseas. But the Romney campaign is standing by the ad.
Obama told Ohio voters that Jeep plant workers were calling their bosses to ask if they were going to lose their jobs. He said Romney was playing a game with people's lives to try to win the election.
"So you don't scare hard-working Americans just to scare up some votes," Obama said. "That's not what being president is all about. That's not leadership."
Each candidate got new evidence to bolster his closing argument from Friday's economic report showing more job creation and an uptick in unemployment. The Labor Department reported that U.S. employers added 171,000 jobs in October and that hiring was stronger over the previous two months than first thought. The unemployment rate inched up to 7.9 per cent from 7.8 per cent in September because the workforce grew.
As an economic marker, the report sketches a picture of a job market that is gradually gaining momentum after nearly stalling in the spring. As a political marker, it gives Romney a data point to attack. Obama will face voters with the highest unemployment rate of any incumbent since Franklin Roosevelt.
"We are four days away from a fresh start," Romney said in a speech in West Allis, Wis. The former Massachusetts governor rarely speaks from prepared text at his political rallies but was doing so as he delivered a new final pitch.
Romney ticked through his achievements, building one business, turning around another, putting the Olympics back on track and political cooperation with a Democratic Legislature.
He warned that an Obama re-election would threaten another government shutdown and national default.
"I know when I am elected, the economy and the American job market will still be stagnant, but I won't waste any time complaining about my predecessor," Romney said. "I won't spend my effort trying to pass partisan legislation that's unrelated to economic growth. From Day One, I will go to work to help Americans get back to work.
Although the jobs report alone is unlikely to sway voters, it comes amid other signs that the economy is on the mend. Most important, consumer confidence is at its highest level since February 2008, according to the Conference Board. Other signposts this week showed auto companies with sales gains in October and increases in factory orders and production.
"We've made real progress, but we are here today because we know we've got more work to do," Obama said. "Our fight goes on."
Ohio loomed large on the campaign calendar on Friday, with both sides trying to motivate every voter they can. Obama reached beyond the big cities and concentrated on smaller venues, while Romney was holding larger rallies up to an evening kickoff for the final campaign weekend with running mate Paul Ryan, their wives and performer Kid Rock.
"This will probably be a turnout election," Romney told about 1,000 supporters who waited outside the pavilion where he spoke in Wisconsin because they couldn't fit into the room.
But while Ohio was emerging as the most contested state in the final push, Romney and the Republican Party were launching a new drive into Pennsylvania, which had been considered safely in Obama's column. Romney planned to campaign there on Sunday and the Republican National Committee was putting $3 million in ads into Pennsylvania.
Romney aides said they detected that Obama was underperforming in the southeastern counties around Philadelphia, a usual Democratic stronghold, and in the working-class area in and around Scranton. Obama won the state handily in 2008, largely on the strength of his performance in the eastern part of the state. The RNC, however, says its voter outreach program has already exceeded its performance four years ago, with three times more phone calls and 19 more door knocks than at this time in 2008.
Obama aides dismissed the eleventh-hour move as an act of desperation that underscored Romney's weakness in other battlegrounds but said the Democratic campaign would increase its ad purchases in the state to respond to the RNC incursion.
Amid all the signs of escalation, there also were signs that Election Day was nigh.
Outside the White House, workers had begun erecting fencing on Pennsylvania Avenue, setting the groundwork for building the inaugural viewing stand and the camera platform in nearby Lafayette Park.