Limit the after-tax value of certain tax breaks: Lawmakers could enact an after-tax cap that applies to itemized deductions, plus the child tax credit and the tax-free benefit workers receive when their employer helps pay for their health insurance.

A cap set at 2% of one's adjusted gross income or $10,000, whichever is less, applied only to households making more than $200,000, could raise more than $860 billion over 10 years, according to the Committee for a Responsible Federal Budget.