The federal government provides a wide array of special
exemptions, credits and deductions that amount to more than a
$1.1 trillion a year windfall benefiting most Americans.  They
are designed to reward or encourage certain behavior, such as
buying a home, saving for retirement, encouraging employers to
provide health insurance, and other goals.  Most of them have
large built-in constituencies that make them politically
difficult to change or eliminate.  Republican presidential
nominee Mitt Romney says he would target some of these so-called
tax expenditures for elimination to help offset the cost of his
proposed across-the-board tax rate cuts. But neither Romney nor
other Republican leaders have specified which of these tax
breaks they would be willing to eliminate to advance their plans
for major tax reform.  Here is a list of the ten most popular
and expensive tax expenditures, along with the Office of
Management and Budget estimates of their cost to the Treasury in
lost revenues for fiscal 2012:    More