Abraham Lincoln was the second man nominated as the candidate for the Republican Party. The first was John C. Feemont in 1856. The Republicans separated themselves from the Whigs over the issue of slavery.
The expected front-runner for the 1860 Republican nomination was William H. Seward of New York. If they had chosen any place other than Chicago for their convention, Seward may have won. The convention was held at the Wigwam, a wooden convention hall that was built soon before and burnt down soon afterwards. The Wigwam was located on Wolf's Point the northeast shore of the convergence of the North and South branches of the Chicago River. It is now a parking lot.
Lincoln, who had lost the race to Stephen A. Douglas for the Illinois seat in the Senate, but had made a national name for himself in the famous Lincoln-Douglas debates, had dithered on the decision to run for president. Joseph Medill, publisher of the Chicago Tribune, credited himself for convincing Lincoln to run. It wasn't until the favorable reception of Lincoln's Cooper Union Address speech in New York 1860, that Lincoln decided to run.
The six-foot, redheaded mayor of Chicago, "Long John" Wentworth also hoped for the nomination. Credentials were challenged - and forged - claques were paid to shout down opposition speakers, and 'spontaneous' torchlight parades appeared and disappeared. When Wentworth early on realized he was not going to secure the nomination, he put his support - and all of his shenanigans - behind Lincoln.
Stephen A. Douglas, also from Illinois, was the Democratic Party front-runner in 1860 at their convention in Charleston, South Carolina. The Democrats could not reach a consensus and the convention was adjourned without nominating a candidate. When the convention was re-convened in Baltimore, Maryland, Douglas won on the second ballot. The cost was that many Southern Democrats walked out of the convention. Two other Democratic candidates, John Bell and John C. Breckinridge, split the Democratic vote three ways, thus ensuring the election of Lincoln.
After Lincoln's election, he named Seward as his Secretary of State. Seward negotiated the purchase of Alaska from Russia, known at that time as "Seward's Folly".
An interesting historical note is that John Bell's running mate, Edward Everett, later gave the two hour speech at Gettysburg that overshadowed Abraham Lincoln's two hundred and seventy-eight word Gettysburg Address, of which the world did, in fact, note and did long remember. Everett's words are not remembered.