Representative Dave Camp, chairman of the House Ways and Means Committee, will release a draft bill this week that's being closely watched by corporate lobbyists and lawmakers. The plan will point up the tradeoffs in reshaping the tax code and altering U.S. tax breaks for retirement, housing, energy, charity, health care, capital gains and finance.

"It gives people a chance to see in stark relief what it takes to get a broader-based, lower-rate code," said Jonathan Traub, a former senior aide to Camp. "It's incredibly difficult. There are few provisions in the code that are sort of broadly agreed by everybody to be loopholes. A rate reduction benefits everybody, but it's very expensive."

The plan has little chance of becoming law this year. Even so, the response from lawmakers, business groups and the public will test an idea that has been at the center of Republican economic policy.