Kevin Williamson has a column for National Review arguing against the proposition that we should eliminate the budget deficit entirely by taxing the rich -- a proposition held by nobody of any consequence. Part of Williamson's argument is that the rich already pay close to 50% of their income in taxes already ("Most of them are making $250,000 to $450,000 and paying about half in taxes already.")
Robert VerBruggen echoes Williamson's point ("the other half is already taken in federal and local taxes.")
Are the rich really paying half their income in federal, state and local taxes? No, they're not:
Again, it's certainly true that it would be very difficult to eliminate the deficit entirely by taxing the rich. But you could certainly make a sizable dent in the deficit this way.