The Obama Administration’s budget proposal for 2013 would reduce the percentage value of itemized deductions (including the charitable contribution deduction) to 28 percent of adjusted gross income for families with incomes above $250,000, and individuals earning more than $200,000. The tax rate for upper income taxpayers would be raised to 39.6 percent.

The administration pointed out that “there’s still a tax benefit for every additional marginal dollar contributed, so there is still an incentive to keep giving to charities.”