if your unable to support yourself or your family I would say that would be considered low income, it's differ for every state but as long as your not abusing the system I believe even in this rotten economy you will still be able to find the help you need. good luck
In the US, low income is considered to be around $25,000. However, it also depends with the state or the job one does. For example, these numbers drop in California's less-affluent enclaves like Bakersfield, Chico and Fresno.