Uncle Sam’s sterling credit rating has survived a major downgrade by Fitch – for now. The ratings agency said Monday it will keep the U.S. credit rating at AAA but lowered its outlook. Days after a congressional supercommitte failed to strike a deal on shaving $1.2 trillion in deficit cuts over the next decade, Fitch said it saw a 50 percent chance the firm would downgrade long-term U.S. debt in the next two years. "By postponing the difficult decisions on tax and spending until after forthcoming congressional and presidential elections, the scale and pace of required deficit reduction will consequently be greater," Fitch said. Back in August, another ratings agency, Standard and Poor's, downgraded U.S. debt a notch below AAA for the first time ever.