If a simple majority fails to approve at least $1.2 trillion in debt reduction — or Congress votes down the group’s proposals in December — that could put serious downward pressure on the U.S. sovereign credit rating.

The three major credit ratings agencies, which declined to comment for this article, basically put Congress on notice after the debt-ceiling nightmare this summer…

If the super committee process fails, in theory, $1.2 trillion in automatic spending cuts would be triggered. But many seasoned observers expect Congress may end up modifying or repealing that trigger.

By contrast, if the super committee process succeeds and Congress votes through more than the minimum $1.2 trillion in savings, S&P said that could help to stabilize the country’s long-term AA+ rating.