Answer: The Election of 1860
The election was unusual because four strong candidates competed for the presidency. Political parties of the day were in flux. The dominant party, the Democratic Party, had split into two sectional factions, with each promoting its own candidate.
With such confusion among the ranks, it was unclear how the Democratic Party would ever nominate a candidate for the 1860 election. But on April 23, 1860, they met in Charleston, South Carolina to decide their platform and identify a nominee.
Stephen Douglas was the frontrunner, but Southern Democrats refused to support him because he wouldn’t adopt a pro-slavery platform. Many walked out in protest, leaving the remaining delates without the majority needed to nominate Douglas; the convention ended without a nominee.
I hope this helps you! :) have an amazing day! ^-^