The election was between Buchanan and Republican John C. Frémont in the north and between Buchanan and Millard Fillmore, nominated by a pro-slavery faction of the Know Nothings, in the South [REF].
Despite irregularities in the approval of the Lecompton Constitution by Kansas voters, Breckinridge agreed with Buchanan that it was legitimate, but he kept his position secret, and some believed he agreed with his friend, Stephen Douglas, that Lecompton was invalid [REF].