>> Are you counting the giant companies that get tax breaks?

Or TARP?

Actually, I'd guess it's a lot more than 50%.
Just about all seniors get Social Security and/or Medicare and/or Prescription Drugs (which they pay for.)
With unemployment over 7% there are lots of people collecting unemployment.
Add Veterans Benefits, Federal, State and Local pensions, Welfare, Head Start, Food Stamps, Earned Income Tax Credit, etc and you have a lot of people getting money from Federal and/or State programs.

Unfortunately, the revenue side has been decreasing since Reagan began reducing marginal rates and Bush ramped it up even further.