I’ll begin this by stating the obvious: modern-day Democrats are far more likely to be anti-Semitic than modern-day Republicans (almost 2:1). In fact, current Democrats are far more likely to be anti-Semitic than Republicans ever were. Study referenced here:
http://www.wnd.com/2003/01/16744/
That said, you asked about history. There are not a lot of studies like the one posted above on history, so I’ll just give some examples:
Sen. Prescott Bush (grandaddy) was on record for his anti-Jewish statements, on the board of a Nazi-controlled bank, and was almost prosecuted for “trading with the enemy.” (The details of all but his opinions are controversial and from lefty sources, so take any given specific with a grain of salt.)
James Baker is famous for wanting to abandon Israel (”F—k the Jews.”) because American Jewish voters “didn’t vote Republican.”
http://pamelageller.com/2006/12/james_fuck_the_.html/
Henry Ford was a classic Republican anti-Semite and the Republicans of the day including some noted anti-Semites.
Etc.
What really brought Republicans “around” to liking Jewish people and Israel was William F. Buckley, and I think Buckley conservatism is the type of conservatism that Jews will eventually embrace.
Pat Buchannon of today represents the last gasp of Republican anti-Semites.
I knew Ford was anti-Semitic.