For the first time in over a month, the twelve member Joint Committee on the Deficit will hold a hearing on their work, hearing from the head of the Congressional Budget Office on spending issues.

It's the second time that Elmendorf has testified - in just three hearings held by the so-called Super Committee; in his first appearance, he laid out a blunt bottom line for lawmakers.

"The federal government is confronting significant and fundamental budgetary challenges," Elmendorf said on September 13.

"The task of addressing those formidable challenges is complicated by the weakness of the economy and the large numbers of unemployed workers, empty houses, and underused factories and offices," the CBO chief added.

Since a late September hearing, the Super Committee members have been almost silent, saying little in the hallways and even giving their leadership few indications of what they're up to.

Elmendorf's appearance comes a day after the CBO issued a report on household income, which seems certain to be trumpeted by Democrats in coming weeks to argue that top income earners should pay more in taxes.

The CBO found that between 1979 and 2007: