Twenty-five top fictional presidents

At B&N Reads Tara Sonin tagged twenty-five fictional presidents. One entry on the list:
Lucy, by Ellen Feldman

[T]his novel is about a president who was in love with someone who wasn’t his wife. Before he was President, Franklin Delano Roosevelt loved Lucy Mercer…Eleanor’s social secretary. Through polio, a world war, and two presidential terms, despite his promises to Eleanor, Franklin and Lucy