The United States government, and in particular elections, are so heavily influenced by corporate money that they are almost not to be trusted. Oversight and close monitoring from international organizations such as the United Nations could be a useful tool in ensuring that the rights of the voters are in fact being upheld.
No, it is my belief that the USA does not need extra, outside help to monitor elections. There should be no need for outside help to help a countries personal and private elections. I think that the methods to vote that are set up right now are perfectly adequate for counting valid votes, and thats all that matters.
No, the U.S. is capable of monitoring its own elections and does not need outside help. As an independent democracy, it is the duty of the U.S. to ensure that all elections, whether local or general, are conducted securely and fairly. Allowing the intervention of an outside party puts the objectivity and safety of the election in jeopardy, as another entity may have its own self-interests in mind rather than those of the nation.
The only reason this is even an issue right now is because Donald Trump keeps bringing it up during his rallies. He's afraid that he's going to lose and he has such an inflated ego that he has to make up some crazy story about the election being rigged to make up for his obvious shortcomings.