Washington Post Updated 12:05 a.m., Friday, September 7, 2012 President Barack Obama speaks during the Democratic National Convention at the Time Warner Cable Arena in Charlotte, N.C., Sept. 6, 2012. (Luke Sharrett/The New York Times) (LUKE SHARRETT / New York Times) CHARLOTTE, N.C. -- President Barack Obama appealed to the nation Thursday night for another four years in office, asserting his policies are returning the country to economic prosperity. The president outlined a series of second-term goals he said would cut the deficit, increase manufacturing jobs, reduce dependence on foreign oil and slow the growth of college costs. Obama said the choice between him and Republican Mitt Romney represents the clearest in a generation, a choice between sharply contrasting visions and political philosophies. But after entering office in January 2009 amid outsized expectations, he cautioned that the path he offers may be hard but will lead to "a better place." "The truth is, it will take more than a few years for us to solve challenges that have built up over decades," he said. "It will require common effort, shared responsibility and the kind of bold, persistent experimentation that Franklin Roosevelt pursued during the only crisis worse than this one." The speech wrapped up a Democratic National Convention that combined a withering critique of Romney with a defense of the president's record that Obama's campaign team members hope will tip a closely fought election in their direction by November. The president spoke directly to the disappointment among some of those