Mr. Romney’s top economic adviser, Glenn Hubbard, said the plan would cut all six current tax brackets — 10, 15, 25, 28, 33, and 35 percent, depending on a taxpayer’s income — by the same proportion of 20 percent. That would produce this new set of tax brackets: 8, 12, 20, 22.4, 26.4, and 28 percent. “It’s a marginal rate cut for every American,” Mr. Hubbard said.
But he added that Mr. Romney is committed to making his plan both “revenue neutral” – meaning it won’t add to the budget deficit — and “distributionally neutral” – meaning that it won’t shift the tax burden from upper-income Americans to middle and working class Americans. Since the largest benefits from rate reduction would go to upper income taxpayers, so will the burdens of “base broadening” reductions in existing deductions needed to keep the government from hemorrhaging revenue, he explained.