explicitly repealed the Missouri Compromise. President Franklin Pierce supported the bill as did the South and a fraction of northern Democrats. The act split the Whigs. Northern Whigs generally opposed the Kansas–Nebraska Act while Southern Whigs supported it. Most Northern Whigs joined the new Republican Party. Some joined the Know-Nothing Party which refused to take a stance on slavery. The southern Whigs tried different political moves, but could not reverse the regional dominance of the Democratic Party. Bleeding Kansas With the opening of Kansas, settlers rushed into the new territory. Both pro- and anti-slavery supporters rushed to settle in the new territory. Violent clashes soon erupted between them. Abolitionists from New England settled in Topeka, Lawrence, and Manhattan. Pro-slavery advocates, mainly from Missouri, settled in Leavenworth and Lecompton. In 1855, elections were held for the territorial legislature. While there were only 1,500 legal voters, migrants from Missouri swelled the population to over 6,000. The result was that a pro-slavery majority was elected to the legislature. Free-soilers were so outraged that they set up their own delegates in Topeka. A group of anti-slavery Missourians sacked Lawrence on May 21, 1856. Violence continued for two more years until the promulgation of the Lecompton Constitution. The violence, known as "Bleeding Kansas," scandalized the Democratic administration and began a more heated sectional conflict. Charles Sumner of Massachusetts gave a speech in the Senate entitled "The Crime Against Kansas." The speech was a scathing criticism of the South and the "peculiar institution." As an example of rising sectional tensions, days after delivering the speech, South Carolina Representative Preston Brooks approached Sumner during a recess of the Senate and caned him. The new Republican Party The new Republican party emerged in 1854–56 in the North; it had minimal support in the South. Most members were former Whigs or Free Soil Democrats. The Party was ideological, with a focus on stopping the spread of slavery, and modernizing the economy through tariffs, banks, railroads and free homestead land for farmers. Without using the term "containment", the new Party in the mid 1850s proposed a system of containing slavery, once it gained control of the national government. Historian James Oakes explains the strategy: "The federal government would surround the south with free states, free territories, and free waters, building what they called a 'cordon of freedom' around slavery, hemming it in until the system's own internal weaknesses forced the