King is right here, TTL the biggest post-Civil War migration has been the one West. It was made quicker by the Influenza Epidemic of 1862, which sprang from the South, but apart from that, there haven't been any specifically Southern factors.
PS. Would anyone object to the presidential race getting started late today?
Current Sitrep on Primary:
Federal: Vallejo projected to win by certain analysts, whose sanity has been called into question.
ACP: Lee Davis ahead with 4 to 2. Union veterans and bored youngsters ready pitchforks.
Democratic: Hayden in a three-nil lead on Mr. Nightmore. Alcoholics rejoice.
8/2/0, passing by a wide margin so far.