President Obama, Mitt Romney spar over gas prices President Obama and Mitt Romney traded jabs Wednesday as the threat of greater fluctuations in oil prices drove a long-distance debate over energy policy. Romney said Obama should do more to open up domestic sites for drilling, including the Arctic National Wildlife Refuge in Alaska. "He ought to be taking advantage of all our offshore instead of trying to hold them off," Romney told CNBC. But Obama, speaking to workers at a Daimler truck plant in North Carolina, said Republican presidential candidates weren't offering realistic solutions to reducing the nation's reliance on foreign oil. "As a country that has 2% of the world's oil reserves but uses 20% of the world's oil, we're not going to be able to just drill our way out of the problem of high gas prices," Obama said. Anybody who tells you otherwise either doesn't know what they're talking about or they aren't telling you the truth. The exchange came as Romney reached out to conservative voters and asserted himself as the eventual GOP nominee following Super Tuesday victories that included a narrow but significant win in the swing state of Ohio. His campaign pointed to the volatile price of gasoline as a vulnerability for the Democratic president. In Chicago, Obama campaign officials highlighted what they see as Romney's weakness with middle-class voters. How can you be a candidate who says let Detroit go bankrupt and who disdains manufacturing and who has his history in business of closing down factories and squeezing businesses for the profit of him and his partners but costing jobs? Obama advisor David Axelrod asked reporters. How do you then go back to people in the industrial Midwest and say, 'I'm the leader for you'? Obama spent the day in North Carolina, where a new Elon University poll suggested that he had a tentative relationship with voters worried about the economy. The poll shows that more than 50% of those interviewed disapproved of Obama's handling of economic matters, though his approval rating has been improving along with the economy. Obama urged Congress to approve $1 billion in grants to cities and towns to encourage use of fuel-efficient technology, and proposed increasing tax incentives to spur people to buy fuel-efficient cars. The long-term solution to rising gas prices, Obama said, is to "invest in the technology that will help us use less oil in our cars and our trucks, in our buildings, in our factories." But Romney criticized Obama's energy policies, saying they contributed to an energy shortage. The president can "decide how much money for oil and gas is going to other nations, and to get that money here and to create jobs here and to stabilize prices here," Romney said in the CNBC interview. "He ought to be taking advantage of all of our offshore, and [the Arctic refuge], and North Dakota and Oklahoma and Texas gas resources, instead of trying to hold them off," Romney said. Natural gas is a huge win for us and through the [Environmental Protection Agency] he's been trying to hold that off.