Question

How did the election of 1860 increase sectional tensions?

Answer 1

Prior to the outbreak of the Civil War, the election of 1860 increased sectional tensions of the United States by lifting pro-union, anti-slavery statesman, Abraham Lincoln into the Presidency. In reaction, the Southern States protested in many ways, but in no more dramatic way than, one by one, seceding. 

Answer 2

Because the newly-elected Lincoln would not agree to any extension of slavery. So the final attempt at compromise failed.