This is the 52nd presidential election.
The 18th was held in 1856. It was a tumultuous time. The Whig Party had elected two of the last four presidents, but it found itself riven and reduced to its last gasping breaths by the most volatile issue in American political history, slavery. The Democrats had a problem with this, too. Southern based, the party was strongly pro-slavery. It supported extending slavery into the Western territories. Many Whigs and some Democrats in the North and Midwest switched to the new anti-slavery Republican Party.
Democrats nominated James Buchanan, a bland former diplomat and senator. The remnants of the Whigs united with nativist extremists and nominated former President Millard Fillmore, also bland. The new Republicans nominated a romantic young Western explorer and soldier, John C. Fremont. Southern Democrats warned that their states would secede if the new party won.
Buchanan won with 174 electorals to Fremont's 114, Fillmore's 8. So divided was the nation sectionally that Fremont did not get a single popular vote in 12 Southern and Border states, and Buchanan carried only a few counties above the Mason-Dixon Line.