WASHINGTON (AP) - Who are the "Forty-seven percent of Americans" who Republican presidential candidate Mitt Romney says pay no income taxes?

A study by the nonpartisan Tax Policy Center says 46 percent of U.S. households paid no federal income tax last year.

About 22 percent were senior citizens who got tax breaks that offset their income. Some 15 percent are working poor or low-income parents. And almost 3 percent received tax breaks for college tuition or other education expenses.

The Tax Policy Center says 9 out of 10 households that didn't owe in 2011 made $50,000 or less. But 4,000 households earning more than $1 million a year didn't pay federal income tax.

And who are the people who get federal benefits?

The most recent Census Bureau data says the largest group is the 26 percent of Americans who receive Medicaid. Sixteen percent get Social Security and 16 percent receive food stamps. Medicare goes to 16 percent of the U.S. population and 8 percent are in the Women, Infants and Children food program known as WIC.

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