How many Americans are on welfare?

Around 50.1 million.

In September 2009, around 4 million Americans were served by a state cash-assistance or welfare program, more than 37 million received federal food stamps and about 9.1 million received unemployment benefits. If treated as exclusive numbers, there would be a total of 50.1 million Americans who received federal aid in September 2009. This data is based on a report published in USA today in January 2010.