TIA's link is quite instructive, as are Carol C's comments on what has actually happened.

As to ACORN not being 'non-partisan'...*sigh*... it is perfectly possible to be non-partisan and still have Republican/conservative groups concerned that ACORN's activities in getting out minority voters and helping register folks who had not been voting was NOT in their (Republican) interest!
Of course what ACORN does is likely to help Democratic interests more than Republicans...at least as long as Republicans are more concerned about 'business' than about fairness and voting rights for ALL demographic groups.

When 'winning at all cost' becomes your Mantra, some pretty sleazy tactics suddenly seem 'reasonable'

If you look hard enough at ANY group, you can find individuals whose behavior is questionable. That is hardly evidence that such behavior is either group policy or condoned by management. Why is this so hard to grasp?