This is what happens when you fail to consult the world's most irrelevant, obscure and boring blog:
http://platosbeard.org/archives/257
A link to an EPI (alert: partisan) study of minimum wage hikes independently carried out by states, and the results.
=> Have these state actions had any effect? Are wages higher than they => would have otherwise been, i.e., are these higher minimums reaching => their intended beneficiaries? Is employment worse than it would have => otherwise been? The evidence presented here suggests that the answers => are, respectively, yes, yes, and no.
They have graphs, data, etc. I am not an economist and I found statistics the most boring part of my degree in mathematics, so don't take my opinion for much.
If you want to look for opposing [attempts at] arguments head on over to the Hudson Institute.
--ravi