A clear message must be sent that, regardless of political strata and the intended audience, it is absolutely unacceptable for any racist terms such as "Socialist Jew" to be used towards or about presidential candidates. This is especially the case when there are many eyes on the situation and the public are as informed as they are by the media.
First of all, it is sinful to try to degrade someone for any purpose. Society is changing rapidly, even though it is hard to tell with Donald Trump's divisive rhetoric. This kind of hate speech should not be tolerated. Maybe if the press catches wind of his words it will be broadcasted everywhere and he will face the repercussions.
Although technically speaking the term "Jew" is not racist, it is still an unfair bias. If a person in a position of authority such as the Precinct Captain is allowed to label a presidential candidate with terms that refer not to their deeds, but to their assumed beliefs - whether that assumption is correct or not - then it is not unreasonable to feel these same prejudiced views may be applied to people in a less influential position. This is a terrifying thought that must be stopped before it is allowed to come to fruition. The Captain must be punished for his words with a hope of correcting his unjust thought process.
Americans have the right to free speech - even if it's speech that is hurtful. In fact, freedom of speech exists BECAUSE of unpopular speech. If something is popular, why would it need protection? It would be dangerous to start punishing precinct captains for things that are said. It may start with good intentions -- after all, in this particular case, the precinct captain said something that is very hurtful -- but it could end up escalating to punishing captains just because they said something that a person in power just happened to dislike.
Precinct captains are elected officials. Let the voters decide whether they want this particular person to continue in this position. If the election is still a long ways away, then shorten the term for the position. Regardless, let the voters take care of it. There is no greater punishment for an elected official than losing an election. I doubt that many of the voters would want someone with these types of views to continue to represent them. If the captain says something hurtful enough, then the voters will take care of it. Believe me.