The main issue debated during the 1844 presidential election was whether to annex the slave-holding state of Texas into the union. Democrat James K. Polk supported the annexation and defeated Whig candidate Henry Clay.
Whigs who were slave owners opposed the annexation of Texas because they were afraid the large state would drive up demand and prices for slaves. Whigs who were opposed to slavery were afraid that admitting such a large slave-holding state would tip the union in favor of slavery. Whig nominee Clay also feared that annexing Texas might provoke a war with Mexico, which claimed Texas. Following Polk's election, Texas was admitted to the union in 1845, sparking the Mexican-American War from 1846 to 1848.