In 1910, Hershfield started a strip called Desperate Desomnd, a parody of adventure melodramas in a similar vein as Milt Gross' He Done Her Wrong from two decades later. He incorporated a Yiddish character into the strip, which proved a positive move and Hershfield's editor encouraged him to start a new strip focusing on the Jewish experience in America. Thus, Abie the Agent was born.
Abraham Kabibble* was a car salesman and, while he and the other Jewish characters depicted used some strong elements of Jewish culture to emphasize their roots, Hershfield was careful to avoid using those elements as part of the humor itself. For example...
Abie is clearly speaking a forced dialect, and the two characters have decidedly Jewish-sounding names, but there's no demeaning of the characters because of that. Hershfield is relying on some stereotypes, but not as the focus of the humor itself. He's basically using the strip to showcase that Jewish Americans are pretty much just like other Americans and weren't deserving of the broad slander that was often cast against them at the time. This was further emphasized in 1917 when Abie enlisted in the US Army to fight during World War I.
Clearly, Abie the Agent didn't change the hearts and minds of everybody overnight, and there would still be anti-Jewish sentiment in some circles for years. But being popular enough to have several strip collections made, two animated cartoons, and a reference in the Marx Brothers classic Animal Crackers suggest that it did help many Americans begin to accept and understand Jews as people just like them.
Kind of a pity that newspapers don't have that same pull today; maybe we could get a new version called Abhed the Agent.
* As far as I can tell, this is the first instance of "Kabbible" being used as a Jewish name. Merwyn Bogue wouldn't adopt his "Ish Kabbible" stage name for several more years. There was a 1913 song titled "Isch ga-bibble" which Bogue later claimed to have gotten the name from. Whether Hershfield also got the name from the same song is unknown, but it would seem likely as "kabbible" is not a word itself and the song only debuted the year before Abie the Agent.