White Journal, Page 14, 1856 Missouri Election

At this election there were 3 parties represented, viz National Democrats, Benton Democrats, and American (or Know Nothings)

The 1856 Missouri election for governor came down to three candidates: Trusten Polk, representing the Democratic Party, Robert Ewing of the Know Nothing Party, and Thomas H. Benton of Independent Democratic Party, with a large divide occurring over the issue of slavery. Polk ultimately won, though he resigned from the governorship a year later to run for United States Senate, which he was then removed from due to his secessionist sympathies.