Americans for Tax Reform president Grover Norquist blasted former Republican Sen. Alan Simpson's on Friday, defending his own staunch anti-tax stance in the process.
Norquist - an influential GOP lobbyist and a fierce opponent of raising taxes - dismissed the idea that a pledge to hold the line on taxes was an impediment to reaching a deal on the looming "fiscal cliff."
Responding to strong criticism made earlier this week by Simpson, the architect of a widely praised fiscal blueprint along with former Washington operative Erskine Bowles, Norquist told CNBC: "Alan Simpson ranting is not news."
As politicians get to work on trying to reach a deal to solve the country's fiscal problems, Simpson told CNBC in an interview Thursday that "I've always said about Grover Norquist: is he's wandering the earth in his white robes."
(Read more: "Obamacare, Host of Others Need Slashing: Simpson-Bowles".)
Simpson chided his fellow Republican for sticking to his guns on keeping taxes low, and questioned Norquist's ability to force Republicans to toe his line.
"What can he do to you? He can't murder you, he can't burn your house. The only thing he can do to you is defeat you for reelection. And if that means more to you than your country ... you shouldn't even be in Congress."
Norquist, however, threw cold water on the Simpson-Bowles proposal. The anti-tax advocate said the plan would take taxes as a percentage of gross domestic product from 18.5 percent in full employment - the average over the past 30 years - to 21 percent, which equates to a $5 trillion tax increase over the next decade.
Norquist told "Closing Bell" growth - not tax hikes - is the best way to raise revenue for the federal government.
(Read More: Cut Spending to Fix 'Fiscal Cliff': Norquist.)
"If you grow at 4 percent a year instead of 2 percent a year for one decade, the government raises $5 trillion," Norquist asserted.
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