The Kansas Nebraska Act had determined that the people who lived in each territory would decide the question of slavery. This led both proslavery and antislavery settlers to rush to the new territories in order to sway the vote. In Nebraska, the population was already largely against slavery, and disputes were dealt with peacefully. In Kansas, however, things took a more violent turn. When elections were held, citizens from the border state of Missouri poured over the territory line to vote for proslavery candidates. Attacks were launched, and people on both sides of the struggle were injured and even killed. This period came to be known as "Bleeding Kansas." Peace between North and South seemed to slip further out of reach.
The conflict over the Kansas Nebraska Act in the violence of "Bleeding Kansas" had significant political consequences. The Whig Party, one of the two main political parties in the nation, was torn apart along geographic lines. Every northern Whig opposed the Kansas Nebraska Act, while the majority of Southern Whigs supported it. The party could no longer operate as a single political unit.
Southern Whigs joined the Democratic Party, the other main political party in the nation. Northern Whigs started a new group, they called it the Republican Party. Abraham Lincoln would become the first prominent voice of the Republican Party.