Editing Sam Houston (section)

===Pierce and Buchanan administrations (1853–1859)===
{{see also|Presidency of Franklin Pierce|Presidency of James Buchanan}}
[[File:Sam Houston c1856-59-crop.png|thumb|Houston {{circa}} 1856–1859]]

In 1854, Senator [[Stephen A. Douglas]] led the passage of the [[Kansas–Nebraska Act]], which organized [[Kansas Territory]] and [[Nebraska Territory]]. The act also repealed the [[Missouri Compromise]], an act that had banned slavery in territories north of parallel 36°30′ north. Houston voted against the act, in part because he believed that Native Americans would lose much of their land as a result of the act. He also perceived that it would lead to increased sectional tensions over slavery.{{sfn|Haley|2002|pp=321–326}} Houston's opposition to the Kansas–Nebraska Act led to his departure from the Democratic Party.{{sfn|Cantrell|1993|p=333}} In 1855, Houston began to be associated publicly with the American Party, the political wing of the [[Nativism (politics)|nativist]] and unionist [[Know Nothing]] movement.{{sfn|Cantrell|1993|pp=328–330}} The Whig Party had collapsed after the passage of the Kansas–Nebraska Act, and the Know Nothings and the anti-slavery [[Republican Party (United States)|Republican Party]] had both emerged as major political movements.{{sfn|Haley|2002|pp=340–341}} Houston's affiliation with the party stemmed in part from his fear of the growing influence of Catholic voters; though he opposed barring Catholics from holding office, he wanted to extend the [[naturalization]] period for immigrants to 21 years.{{sfn|Cantrell|1993|pp=330–333}} He was attracted to the Know Nothing's support for a Native American state as well the party's unionist stance.{{sfn|Haley|2002|pp=341–342}}

Houston sought the presidential nomination at the [[1856 American National Convention|Know Nothing party's 1856 national convention]], but the party nominated former President [[Millard Fillmore]]. Houston was disappointed by Fillmore's selection as well as the party platform, which did not rebuke the Kansas–Nebraska Act, but he eventually decided to support Fillmore's candidacy. Despite Houston's renewed support, the American Party split over slavery, and Democrat [[James Buchanan]] won the [[1856 United States presidential election|1856 presidential election]]. The American Party collapsed after the election, and Houston did not affiliate with a national political party for the remainder of his tenure in the senate.{{sfn|Cantrell|1993|pp=340–342}} In the [[1857 Texas gubernatorial election]], Texas Democrats nominated [[Hardin Richard Runnels]], who supported the Kansas–Nebraska Act and attacked Houston's record. In response, Houston announced his own candidacy for governor, but Runnels defeated him by a decisive margin.{{sfn|Haley|2002|pp=344, 352}} It was the only electoral defeat of his career.{{sfn|Campbell|2000}} After the gubernatorial election, the Texas legislature denied Houston re-election in the senate; Houston rejected calls to resign immediately and served until the end of his term in early 1859.{{sfn|Haley|2002|pp=353, 360}}