Obama, Romney shift battleground to Virginia Obama and Romney head to the swing state of Virginia on Thursday Obama leads in the state, but undecided voters make it close Obama and Romney challenge each other on China trade, a key issue in Ohio Latest poll numbers show an uphill battle in swing states for Romney (CNN) -- President Barack Obama and Republican presidential nominee Mitt Romney shift the presidential battleground to Virginia on Thursday, a day after dueling campaign stops in the swing state of Ohio. Obama will visit the Hampton Roads area near the state's coast while Romney heads to Springfield outside of Washington. Polling suggests that while Obama has the lead in the state, it could be a close race. In two out of three recent polls, the margin of error, coupled with the percentage of undecided voters, leaves the state up for grabs for either candidate. A CNN Poll of Polls of likely voters released on September 20 shows Romney behind Obama by six points. Three other polls show an Obama lead, but within the polls' sampling error: a Quinnipiac University/CBS News/New York Times poll shows Obama leading Romney by four points; a Washington Post poll in the same week shows Obama leading by eight points; and a NBC News/WSJ/Marist Poll shows Obama leading Romney by five points. But the NBC News/WSJ/Marist poll and the Quinnipiac/CBS/New York Times poll show 5% and 3% of the respondents saying they're undecided. The Washington Post poll did not list undecided voters. Obama's 2008 victory made Virginia -- historically a Republican stronghold -- a battleground. No Democratic presidential candidate had won the state since Lyndon Johnson's landslide win in 1964. One in eight voters in the state live in Fairfax County, across the Potomac River from Washington and the site of Romney's rally in Springfield. The region trends Democratic -- John Kerry carried it by 33,000 votes despite losing the state by eight points to George W. Bush in 2004, and Obama won it handily in 2008. But Republican Gov. Bob McDonnell won the area two years ago. Political strategists say that the county is the "classic suburban swing vote" -- independent and paying close attention to the election. Obama kicked off his "official" re-election debut at Virginia Commonwealth University, in the heart of Richmond. One of the reasons Obama was able to take Virginia in 2008 was that volunteers canvassed the state far outside the northern stronghold, registering and reaching new voters. Obama won 92% of the African-American vote in the state, while 60% of whites voted for McCain. Romney and Obama on China in Ohio Obama and Romney went head-to-head on in Ohio on Wednesday, stumping around the state and talking to voters about China, taxes, and jobs. Obama outlines plan for the next four years Surveys suggest that Romney has lost his edge on the economy, the centerpiece of his campaign to highlight slow growth, trade tensions and stubbornly high unemployment under Obama's leadership. His campaign pivoted back to the economy Wednesday after two days of campaign themes centered on foreign policy, as tensions over Libya, Iran and Syria dominated headlines and world leaders gathered at the United Nations. He said that as president, he would adopt policies favorable to manufacturing in response to lost employment. Obama steps up Romney jabs in Ohio Obama said Romney's economic policies -- trickle-down economics -- would not work. "I want to keep taxes low for middle-class families and working-class families, but if we want to close the deficit, we have to ask people like me to spend a little bit more," he said. As both Romney and Obama campaigned through Ohio, a Quinnipiac/CBS News/New York Times poll indicated the president leading Romney 53% to 43% among likely voters in the state. It put George W. Bush over the top in his 2004 re-election, and Obama won it four years ago by five points. CNN's Kevin Liptak, Ashley Killough, Rachel Streitfeld and Paul Steinhauser contributed to this report.