The Lincoln Hunters

Blurb

The Lincoln Hunters is a 1958 novel by Wilson Tucker. The novel, set in the year 2578, details the story of a historian from the oppressive society of that year, who travels back in time to record Abraham Lincoln's Lost Speech of May 19, 1856 in Bloomington, Illinois.
It contains a vivid description of Lincoln in the early stages of his career, seen through the eyes of a future American who feels that Lincoln and his time compare very favorably with the traveler's own.
The book is mentioned in 11/22/63, a novel by Stephen King that also centers around time travel and an assassinated president. Furthermore, the protagonist springboards to 1958-the year "Hunters" first ran-to alter the timeline by 1963.