<P> Two major parties dominated the political landscape: the Democratic Party, led by Andrew Jackson, and the Whig Party, assembled by Henry Clay from the National Republicans and from other opponents of Jackson . Minor parties included the Anti-Masonic Party, an important innovator from 1827 to 1834; the abolitionist Liberty Party in 1840; and the anti-slavery Free Soil Party in 1848 and 1852 . The Second Party System reflected and shaped the political, social, economic and cultural currents of the Jacksonian Era, until succeeded by the Third Party System . Frank Towers specifies an important ideological divide: </P> <Dl> <Dd> Democrats stood for the "sovereignty of the people" as expressed in popular demonstrations, constitutional conventions, and majority rule as a general principle of governing, whereas Whigs advocated the rule of law, written and unchanging constitutions, and protections for minority interests against majority tyranny . </Dd> </Dl> <Dd> Democrats stood for the "sovereignty of the people" as expressed in popular demonstrations, constitutional conventions, and majority rule as a general principle of governing, whereas Whigs advocated the rule of law, written and unchanging constitutions, and protections for minority interests against majority tyranny . </Dd> <P> Historian Richard P. McCormick is most responsible for defining the term . He concluded: </P>

Who played a key role in the development of the second party system what new party did he create