Herman Cain is being seen as a serious candidate for the Republican nomination. For that reason, he has become a target of the Democrat smear merchants. The idea behind these "politics of personal destruction" is to plant seeds of doubt in voters' minds, to tarnish a candidate's otherwise sterling reputation. It is very dirty pool, but it's the way the Democrats roll. They are completely ruthless in their quest for power.
I do not believe that Herman Cain "sexually harrassed" anyone, but what if he did?
I could care less if he played grab-ass with the whole steno pool. I'm voting for the man anyway.
It appears the slander was started by Politico, a left wing website pretending to be an objective news source. I had their number many months ago. See here and here.