Pollsters do not directly ask responders who Joe Biden is but the best estimate on the basis of various questions is that roughly 50% know he is Vice President. That’s not so bad. Fewer have a clue about John Kerry or Chuck Hagel. Hegel is probably known by about 20-25%. Compared to these chaps, Hillary Clinton is a rock star. I’ll go out on a limb and guess she is as well known as her husband. That means she is identifiable by more than 2/3 the public. The kingfish of celebrity in politics is surely Barack Obama. He can be identified by at least 90% of Americans. Right up there with George Washington and Abe Lincoln. Of course, celebrity is different from fame. Celebrity is temporary and fame permanent. For example, because of a rash of movies about James Bond, plenty of people know the name but will he be as famous as Sherlock Holmes 50 years from now? If so, his celebrity will have been converted to fame. In 100 years, who will be better known, Obama or William Henry Harrison? Your guess is as good as mine, maybe better because I am prejudiced in favor of Harrison. Harrison died after 32 days in office. He lay in bed for most of that time and, thus, did less damage to the presidency than anybody else before or after. He ranks as our #1 President of all time. Billy Boy also has the distinction of being the last person to be President who was not born an American citizen. He was grandfathered in because he was born before American independence.
So if anybody tells you a person must be born an American citizen to be President, tell him he wrong. If your guy can trot out a birth certificate that shows he was born prior to 1776 and was a Kenyan back then but became a citizen in, say, 1789, he as eligible as Barack Obama.