List of Fictional U.S. Presidents. This is from Wikipedia and it lists fictional American Presidents. It includes party affiliation, brief biography, and the show or book they appeared in. It includes names such as President Lawrence Ivor Randolph from The Brady Bunch in the White House and President Cliff Barnes from Dallas.
From the site:
Since the office of President of the United States is somewhat hallowed, fiction writers often choose to 'invent' a president in their stories to prevent a real one from being possibly insulted, to avoid having their stories become 'dated' over time, for dramatic license, or to provide literary flexibility.
Presidents are listed in alphabetical order by the first letter in their last name.