Blackburn.
I almost hate to historically rain all over your pat, neat little parade, but you've asked for it in this thread.
So here goes.
The "underground railroad" existed mainly to get escaped slaves into Canada.
There were NO "free" states in the US after the passage of the Fugitive Slave Act in 1850.
A slave was a slave was a slave, no matter what patch of US ground he got to, according to the Fugitive Slave Act.
http://www.fordham.edu/halsall/mod/1850fugitive.html
A few years later, none other than Frederick Douglass gave a fiery speech against slavery in Rochester, NY.
In that speech, Douglass rails against the Fugitive Slave Act.
He also rails against a group of Northern ministers who supported slavery and who Douglass sarcastically labels "The Divines."
Douglass also spends much of that speech delivering a verbal smack-down against his audience, who were largely white, northern abolitionists. He smacks them down because they aren't doing anything about the Fugitive Slave Act or the so-called "Divines" who support and condone slavery from their northern pulpits.
Here's that speech.
http://douglassarchives.org/doug_a10.htm
And, oh yeah, perhaps you've heard of the Dred Scott case?????
http://library.wustl.edu/vlib/dredscott/
Slavery was endemic in the US.
Yes, every single state that seceded from the Union in the Civil War was a slave state. Yes, the Confederate Constitution did not allow any Confederate state to ban slavery. Yes, one of the "states rights" at issue was slavery.
But US slaves (In Missouri, Kentucky, Maryland, Delaware, and New Jersey) had to wait for another seven months after the Confederacy ceased to exist before the 13th Amendment freed them.
And here's a bit from the Wikipedia entry on New Jersey.
http://en.wikipedia.org/wiki/New_Jersey
On November 20, 1789 the state became the first in the newly-formed Union to ratify the Bill of Rights.
"Ironically, on February 15, 1804 New Jersey became the last northern state to abolish slavery by enacting legislation that slowly phased out slavery. However, by the close of the Civil War, several African-Americans in New Jersey were still in bondage and New Jersey initially refused to ratify the Constitutional Amendments banning Slavery and granting rights to America's black population."