Complex sentence: Since the election of 1860, the Electoral College had expanded with the admission of Kansas, West Virginia, and Nevada as free-soil states, but due to the American Civil War, no electoral votes were counted from any of the eleven Southern states.
Split into simpler sentences: Since the election of 1860, the Electoral College had expanded with the admission of Kansas, West Virginia, and Nevada as free-soil states, but the electoral process was disrupted by the American Civil War. No electoral votes were counted from any of the eleven Southern states.