In North Carolina, not far from the site of this summer's Democratic convention, Mitt Romney made an appeal to swing state voters disillusioned with President Barack Obama.

"Right now we're finding people across the country that are experiencing some hard times and I think one of the reasons is because we have a president who's installed some of the old liberal policies from the past, and they didn't work then and they sure as heck aren't working now, and they'll not work in the future," Romney said at the Charlotte Pipe and Foundry Company on Friday.

The Charlotte visit by the presumptive Republican presidential nominee comes after Tuesday's Democratic primary produced lagging results for the incumbent president. In a memo titled, "Obama's Disaster in North Carolina," the Republican National Committee laid out what they see as potential inroads for the GOP in November.

"On Tuesday, 21 percent (or 199,426 voters) of those who voted in the Democrat primary chose 'no preference' rather than voting for President Obama. This means more than one-fifth of the president's fellow Democrats chose Anyone-But-Obama on their ballots," RNC Political Director Rick Wiley said in the memo. "The president's unlucky number must be 14, since these nearly 200,000 voters are fourteen times greater than the president's own 2008 win margin of 14,000 votes."

Romney appeared to be directing his economic speech toward blue collar workers who may have helped Obama win the red state in 2008.

"One of the other ideas of the past, and you keep hearing the president talk about this, is that we don't have much energy left. He says that we only have 2% of the world's oil reserves, and you listen to him and you think somehow we're running on empty," said Romney, who added the United States is "energy rich" because of new drilling technology.

The businessman and former governor of Massachusetts also pledged to stand up for Right to Work legislation as president.

"I don't think it's fair for people who are working in a union to have money taken out of their pay check and have that money go into a political action committee where they don't get to choose which candidate gets it. Instead the union boss gets to take their money and give it to the person of his or her choice," he said.