Dear Yankees and fellow travelers; Down south you would be considered priggish if you exclaimed "Oh Crackey!" The southern and correct expression is "By Crackey!".
As well...

Georgia
Origin of Name: Named by James Oglethorpe for King George II
Nicknames: Peach State, Goober State, Empire State of the South and Yankee-land of the South (refer to economic leadership), Cracker State (originally a derogatory term meaning braggarts, as applied to immigrants into Georgia from the mountains of Virginia and North Carolina), Buzzard State (buzzards were once protected by law in Georgia)

Before the Braves, Atlanta had a minor league baseball team named the Atlanta Crackers.
Even today some black folk call white folk "Crackers" but it lacks bite so no one cares.