US presidential candidates Barack Obama and Mitt Romney have embarked on a final frenzy of campaigning, four days before the general election. Mr Obama, the Democratic incumbent, spoke at three events in Ohio, a state that could be decisive in his bid to be elected for a second term. Mr Romney, the Republican nominee, appeared in Wisconsin before moving on to two events in hotly fought Ohio. Opinion polls show the two rivals neck and neck on the final stretch. On Friday, the US Department of Labor said 171,000 new jobs were created in October, which was better than expected. The figures, the last major economic data to be released before the election, also showed the unemployment rate rose slightly to 7.9% from 7.8%. On the campaign trail, the candidates framed the race for the White House as a choice between two different visions of America. "We know what change looks like, and what the governor is offering ain't it," Mr Obama told supporters in Ohio. Speaking soon after the jobs figures were released, Mr Obama added: "We've made real progress, but we've got more work to do." However, Mr Romney told supporters the report was a "sad reminder that the economy is at a virtual standstill". "Candidate Obama promised change, but he couldn't deliver it. I promise change, but I have a record of achieving it," the former Massachusetts governor said. "[Obama] has never led, never worked across the aisle, never truly understood how jobs are created in the economy." The vice-presidential candidates were also on the trail. Democrat Vice-President Joe Biden spent the day campaigning in Wisconsin, while Republican running mate Paul Ryan made stops in Colorado and Iowa before joining Mr Romney at an event in Ohio. First Lady Michelle Obama was also on the stump on her husband's behalf in Virginia. The frantic pace of campaigning is set to continue over the weekend, with the president scheduled to visit four battleground states - Iowa, Ohio, Wisconsin and Virginia - on Saturday alone. He is then due to appear in New Hampshire, Florida, Ohio and Colorado on Sunday, the penultimate day of canvassing. Mr Romney, meanwhile, is heading to New Hampshire, Iowa and Colorado on Saturday - three states that his opponent carried in 2008. The wealthy former businessman finishes his weekend tour with stops in Iowa, Ohio and Pennsylvania on Sunday. Correspondents say the fate of the election boils down to what happens in a small handful of states that either candidate could win. Ohio, with 18 electoral college votes, has been seen by many as the single most critical state of them all. An opinion poll released on Friday by Rasmussen Reports said the candidates were tied there. But the RealClearPolitics.com average of Ohio surveys put Mr Obama 2.4 points ahead. The White House hopefuls were also urging key groups of voters to back them at the ballot box on Tuesday, as a report from the Pew Hispanic Center suggested that about 70% of Latino voters support Mr Obama, over about 20% for Mr Romney. Meanwhile, Mr Obama has been urging his supporters to head to their polling stations early. Last week, the president himself took a break from the campaign trail to cast an early ballot in his hometown of Chicago. It is estimated about 24 million people have already voted.