** FILE ** This March 15, 2013, file photo shows former Massachusetts Gov., and 2012 Republican presidential candidate, Mitt Romney at the 40th annual Conservative Political Action Conference in National Harbor, Md. (AP Photo/Jacquelyn Martin, File)

** FILE ** This March 15, 2013, file photo shows former Massachusetts Gov., and 2012 Republican presidential candidate, Mitt Romney at the 40th annual Conservative Political Action Conference in National Harbor, Md. (AP Photo/Jacquelyn Martin, File)