Final answer:
The illegal voters in Kansas were known as border ruffians (pro-slavery Southerners from Missouri) and Free Soilers (abolitionists from Nebraska and Illinois).
Step-by-step explanation:
The illegal voters in Kansas were known by different nicknames based on their views and home states.
- Pro-slavery southerners from Missouri were known as border ruffians. They crossed the border into Kansas to vote and gained an advantage through voter fraud and illegal vote counting.
- Abolitionists from Nebraska and Illinois were known as Free Soilers. They moved to Kansas to ensure a numerical advantage over the border ruffians and oppose the expansion of slavery.