This territory was created in 1854 by an act which is also named for Nebraska. For 10 points each:
[10e] Name this current state of the US. As a result of that Act, which allowed its citizens to vote on whether slavery would be permitted, a series of violent conflicts broke out which was referred to as "Bleeding [this territory]".
ANSWER: Kansas Territory [or KS]
[10m] This event was prompted by the speech, “The Crime Against Kansas”, which condemned the cousin of its perpetrator. Preston Brooks attacked a certain senator from Massachusetts in this event.
ANSWER: caning of Charles Sumner [accept any answer containing both an implication of being beaten with a cane and Charles Sumner; prompt on partial answers; prompt on beating or similar responses that don't mention canes by asking "With what?"]
[10h] In Sumner's "The Crime against Kansas" speech, he compared this pro-slavery Senator from Missouri to Catiline. This Senator was a leader of the Border Ruffians during Bleeding Kansas and is often erroneously claimed to have been President for one day.
ANSWER: David Rice Atchison