Republican hopefuls target middle-class insecurity as economy improves

By James Oliphant and Andy Sullivan NASHUA (Reuters) - Facing a recovering economy and a tumbling jobless rate, Republican presidential candidates honing their economic message are trying tap into a lingering sense of insecurity among Americans seven years after the global financial crisis. Then, Republican nominee Romney had the luxury of being able to hammer President Barack Obama with an unemployment rate of more than 8 percent. Now, with the jobless rate at 5.5 percent, the 18 Republican Whi