Fueled by book profits, Obama earned almost $7million since 2004, when he was elected to the Senate.

PHILADELPHIA, PA.Fueled almost entirely by book profits, Sen. Barack Obama (D-Ill.) and wife Michelle earned almost $7 million since he was elected to the Senate in 2004, with the couple reporting more than $4 million in income for 2007, according to returns released Wednesday.

The couple reported total 2007 income of $4,238,165, of which $3,943,378 was profit from his best-sellers ”Dreams From My Father” his memoir reissued in 2004 when his political career started to skyrocket and ”The Audacity of Hope, published in 2006.

The Obamas paid $1,396,772 in federal taxes and donated $240,370 to charity in 2007.

Since elected to the Senate in 2004, the Obamas have seen their income shoot up, almost all from books. In 2004 the Obamas reported $207,647 in taxable income; $1.6 million in 2005 (including the book advance); and $983,826 in 2006/

Release of income taxes has become an issue in the presidential campaign.

Obama last month posted on the Internet his returns from 2000 through 2006 and challenged Sen. Hillary Rodham Clinton (D-N.Y.) to disclose her earnings since she and her husband left the White House. Clinton did make public those returns, showing earning of about $109 million since 2000. The Clintons have now released their returns for all their years in public life, going back to Arkansas.

Clintons campaign is now calling for Obama to release his returns to cover his entire public career, going back to his years as a state senator in Illinois in the 1990s. Even if the Obamas release them, there is likely to be no big numbers. Michelle Obama complains on the campaign trail they did not have the money to pay off loans for their Ivy League education until Obamas book advance.