How safe is Obama's middle-class tax cut?

Remember how President Obama vowed during the presidential campaign not to raise taxes on the middle class? That promise has been coming under intense scrutiny lately.

In remarks to the White House press corps Monday, press secretary Robert Gibbs reiterated that Obama has no desire to raise taxes on U.S. families earning $250,000 or less. Gibbs had to work hard to distance himself from the earlier remarks of Obama's top economic advisers indicating that a tax increase was possible.

Some observers are now saying that barring some sort of economic miracle that swells the coffers of local, state and federal governments, Obama may find that cornerstone of his election campaign a hard promise to keep.