Simpson said the report's recommendations are "wonderful because we've irritated everyone in the United States."
The report, authored by Bowles and Simpson, came under fire last week from a broad range of groups, including several tax organizations that faulted the plan for raising taxes across the board even though the brackets were lowered to compensate for the changes.
The former senator also took on Americans for Tax Reform President Grover Norquist for criticizing the report's tax proposals, who has said the Bowles-Erskine plan clearly outlines $1 trillion in net taxes.
"I think Grover Norquist will be irrelevant in a year," Simpson said. "Because if he’s calling this a tax increase, then he’s in Disneyland."
Bowles and Simpson also backed their 15-cent gas tax, arguing it's the only way to pay for infrastructure spending.
Bowles went after former Speaker Newt Gingrich, who has said capping discretionary spending for several years and eliminating earmarks will lead to a balanced budget.
"He knows better than that. He knows the arithmetic," Bowles said.
Since Bowles and Erskine released their report, a slew of other new proposals have been released, including two from panel members — Rep. Jan Schakowsky (D-Ill.) and the Brookings Institution's Alice Rivlin, who authored a plan with Pete Domenici.
Despite the criticism, the fiscal commission's leaders were still feeling confident about getting the 14 of 18 votes needed to send the plan to Congress.
"We feel like we've got a shot at it," Bowles said. "We've got a chance. If we get 14 votes great — if we don't, then by God, we put it out there."