 In the election of 1860, the Republicans swept Abraham Lincoln into the Presidency and his party took control (with only 39.8% of the popular vote) and legislators into Congress.The states of the deep South, convinced that the economic power of what they called "King Cotton" would overwhelm the North and win support from Europe voted to seceded from the U.S. (the Union).They formed the Confederate States of America, based on the promise of maintaining slavery.