WASHINGTON - US President Barack Obama and wife Michelle made significantly less money last year than in 2009, with book sales their main source of income, according to their joint tax return released by the White House on Monday.

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The first family reported an adjusted gross income of $1,728,096 and paid federal taxes of $435,770, down from income of $5,505,409 in 2009. April 18 was the deadline this year for Americans to file their annual tax returns.

Obama's Democrats are fighting with Republicans over cutting the US deficit through a mixture of spending cuts and tax hikes, with Obama, a best selling author, arguing that wealthier Americans like him can afford to pay more in tax.

Specifically, he opposes extending Bush-era tax cuts on families making more than $250,000 a year. These tax cuts are due to expire at the end of 2012, when they would revert to 39.6 percent from a 35 percent top income rate at the moment.

Earnings from Obama's books, "Dreams From My Father," "The Audacity of Hope" and "Of Thee I Sing" generated $1.568 million last year, according to the couple's tax return.

After-tax proceeds from the last book, which was the only one written after he became president in January 2009, were donated to the Fisher House Foundation to assist military families, which received $131,075 from the Obamas last year.

Overall, the first family gave $245,075 to charity in 2010, reaching out to 36 different charities of which Fisher House was the largest single beneficiary.

Other donations ranged from $1,000 to the $15,000 given to The Clinton Bush Haiti Fund, which the two former presidents promoted in a joint appearance for Haiti earthquake aid with Obama at the White House last year.

Obama reported income from wages, salaries and tips of $395,188 last year. The first family also paid $51,568 in state income tax in Illinois.

Vice President Joe Biden and wife Jill reported adjusted gross income of $379,178 in 2010 and paid $86,626 in federal taxes. They donated $5,350 to charity, the White House said.