The majority of Jews in the Cincinnati metro area, almost all of German rather than Eastern European origin, who arrived on the fruited plain in the 19th century, still vote majority Pubbie to this day. One of their progeny, served as a Pubbie congressman from Cincy not so long ago. I love studying ethnic politics. It is a hobby of mine, and gives me great pleasure.
There were several waves of Jewish immigration, although there have been Jews in America since the very first (possibly a few secret Jews even sailed with Columbus, if you can believe that and a few settled New Mexico). German Jewish immigrants tended to be wealthier and better-educated on average. Also, they assimilated much better, as they came in a smaller group and were able to assimilate well, while maintaining their own identity. Quite a few German and French Jews settled in the South, where they got along quite well. They also settled in the more (at that time) settled parts of the mid-west.
In fact, the first 3 Jewish senators were from the South, if I recall correctly.