People are most often stereotyped or judged as a group. Blacks, Hispanics, Asians, Hells Angels, Baptists......... Consequently, when you belong to a group that collectively exhibits certain characteristics, you are judged by them.
Without going back in history, let's look at Jews today. They are generally successful, educated, resourceful, tenacious and some people say obnoxious, but they certainly exhibit far better social statistics than most of their peers.
So why do so many people hate them? I'm not sure, but I'd guess jealousy plays a pretty big part. Don't forget that much of the world hates us Americans too, even though we see ourselves as pretty good folk.
I think Jews are successful because more then any other "group" they stress education. I went to a school theat was about %95 Jewish and man did they work hard at their education. Not much on sports but very hard on their studies. Parents pushed it.