[arrogantsob]

Divisions in the North were produced by the Democrat Party, Copperheads. They led the Draft Riots in New York which slaughtered any Black the rioters got their hands on even trying to murder the children in an orphanage.

As for as I no the numbers of Northerners enlisting in the CSA army were lowerer than the reverse.

[count-your-change]

I wouldn't over look Lincoln himself a divisive factor with issuance of The Emancipation Proclamation. Presumably any state that had slave and joined the North would be allowed to keep its slaves to the detriment of the white workers.
Naturally the abolitionists wouldn't accept such an idea either.
Lincoln's own attitude toward blacks demonstrates that the Proclamation wasn't based upon distaste for slavery as much as a war time measure against the South.
Further given his treatment of any that spoke against his policies shows that divisions in the North cannot all be laid at the feet of any one group.
And the draft riots show there was a full measure of racism in the North too and it had been written into laws that Lincoln himself supported.