The Liberty Party was an American abolitionist party that existed from 1840 to 1848. The party was founded in 1839 by a small group of abolitionists, and, in 1840, they nominated former slaveholder turned abolitionist James G. Birney as their presidential nominee. The Liberty campaign of 1840 was lost in the excitement surrounding the candidacy of William Henry Harrison, and fewer than 7,000 Americans supported Birney. He failed completely to attract a significant number of abolitionists, who numbered 250,000 at the time. The inexperience and naivete of the Liberty leaders and the abolitionists' traditional opposition to political activity of any kind meant that significant third-party agitation still lay in the future.
The Liberty Party grew slowly during the next four years. Most northerners were not yet ready to face the slavery issue, and the party took no stand on any major issues such as the tariff, the national bank, public lands, and internal improvements. The party spoiled the 1844 presidential election for Whig candidate Henry Clay, as the Liberty Party took 15,800 votes, while the Democrat James K. Polk won the state by a narrow margin of 5,100 votes; if the Libertyites had voted for Clay, he would have won New York, and, therefore, the minimum number of electoral votes needed to win. The party ran on the new platform of the absolute and unqualified divorce of the general government from slavery, claiming that the US Congress had no authority to establish the institution in the territories or continue it in Washington DC. The party openly opposed the annexation of Texas, taking up an anti-extension position. Soon after the election ended in defeat, Birney's followers began urging his nomination for 1848, but Chase and Gamaliel Bailey were better prepared to resist. Chase favored a coalition with northern Democrats, hoping to obtain an agreement with anti-extension elements of the major parties. In 1848, Chase and many moderates merged with other moderates to form the Free Soil Party.