Last-minute debt-ceiling debate was 'embarrassing,' says Dem senator

McCaskill said she believes that if federal spending is cut too rapidly as Congress continues to wrestle down the deficit, it could send the American economy into a tailspin. 

"We're walking a tightrope here," she warned. "If we turn off the lights in terms of federal spending, we will drop off the cliff.”

The overall debt-limit agreement will cut the federal deficit by nearly $1 trillion over 10 years while raising the debt ceiling by at least $2.1 trillion through 2012.

Congress cleared that deal last Tuesday, just hours before the U.S. was projected to begin defaulting on its financial obligations.