Another contributing factor was the money and influence behind the completion between the railroad companies to connect to the west coast.
Before Lincoln, “Secretary of War Jefferson Davis (who later became president of the Confederate States of America) initiated the task of surveying western routes to the Pacific Coast.
There were eight options put forth running along various, north-to-south parallels. Due to the ongoing issue of “slavery” Congress could not agree on which.
As a result the entire undertaking remained dormant for years. As tensions between northern and southern states grew it reached a crescendo when Abraham Lincoln was elected president on November 6, 1860.
With the nation’s fracturing, northern leaders settled on the central option although its construction did not begin until 1862 and was not finished until May 10, 1869.”
https://www.american-rails.com/1850s.html
Corporate corruption was a thing back in 1860, and I will remind everyone that Lincoln was an unethical corporate railroad lawyer at the time.
He used his railroad connections to transport thousands of astroturf "supporters" into the Chicago convention in 1860. That's how the crooked SOB got the nomination over nationally recognized and nationally favored William Seward.
He also used threats and bribery against the convention delegates. There is a lot of ugly stuff about Lincoln that people nowadays have never learned.