The Constitutional Union Party was a United States third party active during the 1860 elections. It consisted of conservative former Whigs, largely from the Southern United States, who wanted to avoid secession over the slavery issue and refused to join either the Republican Party or the Democratic Party. The Constitutional Union Party campaigned on a simple platform "to recognize no political principle other than the Constitution of the country, the Union of the states, and the Enforcement of the Laws".

The Whig Party was a political party that existed in the United States during the mid-19th century. Alongside the slightly larger Democratic Party, it was one of the two major parties in the United States between the late 1830s and the early 1850s as part of the Second Party System. Four presidents were affiliated with the Whig Party for at least part of their terms. Other prominent members of the Whig Party include Henry Clay, Daniel Webster, Rufus Choate, William Seward, John J. Crittenden, and John Quincy Adams. The Whig base of support was centered among entrepreneurs, professionals, planters, social reformers, devout Protestants, and the emerging urban middle class. It had much less backing from poor farmers and unskilled workers.