Obama made $4 million last year

Just hours before tonight's big Pennsylvania debate, Barack Obama kept his pledge to release his income tax return for 2007.

It shows that he and his wife Michelle earned more than in previous years -- more than $4.2 million, with about $261,000 from salaries and the rest from book royalties.

The return also shows that the couple paid nearly $1.4 million in federal taxes and gave about $240,000 to charity.

While in the upper echelon of taxpayers, the Obamas' income still pales in comparison to the estimated $20 million that Hillary and Bill Clinton reported earning last year.

The two Democratic presidential contenders have now released all their tax information for this decade. John McCain, the presumptive Republican nominee, still has not released his returns.

The Clinton camp is still pressing Obama to disclose his returns for 1997, 1998, and 1999 -- years while Obama was serving in the Illinois state senate.