What is the northern view about kansas nebraska act?

Answer 1

The Kansas-Nebraska act opened up the possibility of new slave states made from the former Louisiana territory north of (most of) the southern border of Missouri, which had been forbidden by the earlier Missouri Compromise that allowed Missouri to be formed as a slave state but restricted future slave states to lie entirely south of (most of) Missouri.

By the way: I keep saying "most of" because the southeastern part of Missouri has a "boot heel" that dips further south than the rest of the state. I'm not talking about that part, I'm talking about the southern border of the southwestern part of the state.

Abolitionist were not entirely happy about this, but the prevailing sentiments in the northern portions of the former Louisiana Territory were mainly anti-slavery anyway, so allowing popular sovereignty to determine whether slavery would be allowed or not didn't actually hurt anything in practice...

Until pro-slavery interests began "stuffing" the new territories with people who would vote to allow slavery at the time of statehood. And then abolitionists began doing a little stuffing of their own. In Kansas in particular (see "Bleeding Kansas") some of the stuffing took the form of stuffing guns into people's faces.

Answer 2

It provided an opportunity to gain more slave states if slave-friendly settlers could win the popular sovereignty initiatives.