Question: Which political party was founded to combat the act that lead up to Bleeding Kansas?

Context paragraphs:
History of the United States Republican Party: The Republican Party, also commonly called the GOP (for "Grand Old Party"), is one of the world's oldest extant political parties.  It is the second oldest existing political party in the United States after its primary rival, the Democratic Party.  It emerged in 1854 to combat the Kansas–Nebraska Act, an act that dissolved the terms of the Missouri Compromise and allowed slave or free status to be decided in the territories by popular sovereignty.  The Party had almost no presence in the Southern United States, but by 1858 in the North it had enlisted former Whigs and former Free Soil Democrats to form majorities in nearly every Northern state.

Animal Justice Party: Animal Justice Party (AJP) is a political party in Australia representing an animal rights perspective in the Australian political arena.  On 3 May 2011, the Animal Justice Party was approved by the Australian Electoral Commission (AEC) and AJP was federally registered as a political party under the Commonwealth Electoral Act 1918, making the party eligible for federal funding.  AJP is the first political party in Australia formed to advance animal rights issues.

Marais des Cygnes massacre: The Marais des Cygnes massacre ( , , or ) is considered the last significant act of violence in Bleeding Kansas prior to the outbreak of the American Civil War.  On May 19, 1858, approximately 30 men led by Charles Hamilton, a Georgian native and proslavery leader, crossed into the Kansas Territory from Missouri.  They arrived at Trading Post, Kansas, in the morning and then headed back to Missouri.  Along the way they captured 11 Free-Staters, none of whom were armed and, it is said, none of whom had participated in the ongoing violence.  Most of the men knew Hamilton and apparently did not realize he meant them harm.  These prisoners were led into a defile, where Hamilton ordered the men to shoot.  He even shot and fired the first bullet himself.  Five men were killed.

Kansas Republican Party: The Kansas Republican Party is the state affiliate political party in Kansas of the United States Republican Party.  The Kansas Republican Party was organized in May 1859 and has been the dominant political party of Kansas ever since.

Kansas–Nebraska Act: The Kansas–Nebraska Act of 1854 (10 Stat.  277 ) created the territories of Kansas and Nebraska and was drafted by Democratic Senator Stephen A. Douglas of Illinois and President Franklin Pierce.  The initial purpose of the Kansas–Nebraska Act was to open up thousands of new farms and make feasible a Midwestern Transcontinental Railroad.  The popular sovereignty clause of the law led pro- and anti-slavery elements to flood into Kansas with the goal of voting slavery up or down, resulting in Bleeding Kansas.

Sacking of Lawrence: The Siege of Lawrence occurred on May 21, 1856, when pro-slavery activists attacked and ransacked the town of Lawrence, Kansas, which had been founded by anti-slavery settlers to help ensure that Kansas would become a "free state".  The incident made worse the guerrilla war in Kansas Territory that became known as Bleeding Kansas.

Pottawatomie massacre: The Pottawatomie massacre occurred during the night of May 24 and the morning of May 25, 1856.  In reaction to the sacking of Lawrence, Kansas by pro-slavery forces, John Brown and a band of abolitionist settlers—some of them members of the Pottawatomie Rifles—killed five settlers north of Pottawatomie Creek in Franklin County, Kansas.  This was one of the many bloody episodes in Kansas preceding the American Civil War, which came to be known collectively as Bleeding Kansas.  Bleeding Kansas was largely brought about by the Missouri Compromise and the Kansas–Nebraska Act.

Aboriginal Peoples Party of Canada: The Aboriginal Peoples Party of Canada (APP) is a Canadian political party that was founded in 2005.  The party was conceived by University of Lethbridge student Myron Wolf Child.  It held its founding meeting on August 21, 2005, in St. Albert, Alberta.  The APP was headed by interim leader Bill Montour, a former Chief of the Six Nations Reserve in Ontario.  In October 2005, the party had 122 confirmed members, just less than half the number needed to register as an official party in Canada.  In late October 2005, the APP sought to unite with the First Peoples National Party of Canada which also had fewer than the number of confirmed members needed to become a registered political party.  The First Peoples National Party of Canada became an eligible political party on December 6, 2005.  Whether or not this was accomplished through a merger with the APP is unclear.  If this is the case, the APP no longer exists, but, as one of the stipulations of a possible merger was that a name for the new party would be determined at the party's first convention, it is possible that the name Aboriginal Peoples Party of Canada will come into usage again.

Bleeding Kansas: Bleeding Kansas, Bloody Kansas or the Border War was a series of violent political confrontations in the United States between 1854 and 1861 involving anti-slavery "Free-Staters" and pro-slavery "Border Ruffian", or "southern" elements in Kansas.

United States elections, 1856: The 1856 United States elections elected the members of the 35th United States Congress.  The election took place during a major national debate over slavery, with the issue of "Bleeding Kansas" taking center stage.  Along with the 1854 election, this election saw the start of the Third Party System, as the Republican Party absorbed the Northern anti-slavery representatives who had been elected in 1854 under the "Opposition Party" ticket (consisting largely of former Whigs) as the second most powerful party in Congress.  Minnesota and Oregon joined the union before the next election, and elected their respective Congressional delegations to the 35th Congress.

Supporting paragraphs: History of the United States Republican Party Kansas–Nebraska Act
Answer: The Republican Party