Every day it becomes more manifest that the South will be forced to act as a unit on her right to enter the territories. This must inevitably change the aspect of Parties as they have hitherto existed. Throughout the North, the Whigs and free-soil Democrats will coalesce.
Original passage & context
"Every day it becomes more and more manifest that the South will be forced to act as a unit when the issue shall be made up on her constitutional right to enter and enjoy the territories of this Union [...] Throughout the North, the Whigs and free-soil Democrats will coalesce."
A Georgia paper forecasting the realignment while the bill is still in the House: Whigs and free-soil Democrats fusing in the North, the South voting as a bloc. It expected a large share of Northern Democrats to hold with the South, which is the half of the prediction that did not hold.
Read it in the original — Furman Secession Era Editorials transcription ↗