The fed. website says that the poverty line for a single person is $10,400. States have their own definitions for the thresholds at which someone can qualify for assistance.

I am not sure what you mean by "democrats going at it from the demand side".

In reality, both Dems and Repubs give corporations money to create jobs. Usually, that money comes in the form of big tax breaks or waivers. Haven't you heard about corporations shopping around for the state that will give them the best deal to build a plant? States often spend quite a lot of money since they often have to provide necessary infrastructure, as well.