The Free Soil Party was organized for the 1848 US election to oppose further expansion of slavery into the western territories. It included anti-slavery members of the Whigs, and drew much of its support anti-slavery Democrats, including former President Martin Van Buren.
When the Whigs nominated slave owner Zachary Taylor for president, and took no position on the anti-slavery Wilmot Proviso, prominent Conscience Whigs including Henry Wilson and Charles Allen, withdrew from the party's national convention and issued a call for anti-slavery advocates to meet with the goal of forming a new party. The party included prominent abolitionists such as Salmon P. Chase and John Parker Hale, and held its 1848 convention in Utica and Buffalo, New York. On June 22, Van Buren defeated Hale by a 154-129 delegate count to capture the Free Soil nomination for president, while Charles Francis Adams, the son and grandson of presidents, was chosen as the vice-presidential nominee.
Van Buren knew that the Free Soilers had no chance of winning; he hoped that his candidacy would split the Democratic vote and throw the election to the Whigs. Van Buren pursued this strategy partly from personal animus towards Cass, whom he blamed for preventing him from obtaining the Democratic nomination in 1844, and dislike of the pro-slavery principle of popular sovereignty, which Cass championed. Van Buren's plan proved successful; he obtained enough votes in New York to deny the state to Cass, which was enough to provide Taylor's margin of victory.
Former President
Martin Van Buren
Senator John P. Hale of New Hampshire