Senator Stephen Douglas of Illinois and Abraham Lincoln, a Kentucky-born lawyer and one-time U.S. representative from Illinois, begin a series of famous public encounters on the issue of slavery. The two politicians, the former a Northern Democrat and the latter a Republican, were competing for Douglas' U.S. Senate seat. In the seven Lincoln-Douglas debates--all about three hours along--Lincoln argued against the spread of slavery while Douglas maintained that each territory should have the right to decide whether it would become free or slave. Lincoln lost the Senate race, but his campaign brought national attention to the young Republican Party.
In 1860, Lincoln won the Republican Party's presidential nomination. In that election, he again faced Douglas, who represented the Northern faction of a heavily divided Democratic Party, as well as Southern Democrat John C. Breckinridge and Constitutional Union candidate John Bell. On November 6, 1860, Lincoln defeated his opponents with only 40 percent of the popular vote, becoming the first Republican to win the presidency.
The announcement of his victory signaled the secession of the Southern states, which since the beginning of the year had been publicly threatening secession if the Republicans gained the White House. By the time of Lincoln's inauguration on March 4, 1861, seven states had seceded and the Confederate States of America had been formally established with Jefferson Davis as its elected president. One month later, the American Civil War began when Confederate forces under General P.G.T. Beauregard opened fire on Union-held Fort Sumter in South Carolina.