With tumult raging in Kansas, and torn between an increasing tide of radicalism in both the pro-slave South and the abolitionist North, the Democrats suffered heavy losses in the midterm elections of 1858. The beneficiaries of this sectional rivalry were the Republicans, who picked up seats across the northern and western states, and firmed up their position as a legitimate opposition party.
In a symbolic act that captured the imagination of some and roused the indignation of others, John Brown struck again in October of 1859, this time at Harpers Ferry, Virginia. Already notorious for his massacre at Pottawatomie Creek and a succeeding slave-liberation raid in Missouri, this time Brown made the attempt to seize a federal arsenal with the intention of instigating a slave revolt.
President Buchanan sent in troops at once, and Brown was seized by a company led by Generals Robert E. Lee and J. E. B. Stuart. Summarily tried and executed, Brown became a hero and martyr to abolitionists nationwide. Meanwhile, more moderate politicians like Seward and Lincoln himself denounced Brown for his lawlessness, which to them eclipsed his righteous cause.
When Lincoln learned that the Republican nominating convention for the 1860 elections would be held in Chicago, he decided to officially announce his candidacy for the presidency. This was in fact a calculated political move, done less in the hopes of actual success than out of a desire to win his home state delegates and improve his chances for the 1864 senatorial campaign. However, once in the presidential ring, the momentum began to gather, and after a rousing speech at New York City's Cooper Institute, Lincoln emerged as a definite contender for the nomination. Finding himself a legitimate candidate, Lincoln admitted to a friend that "the taste is in my mouth a little."
Meanwhile, the strife-ridden Democratic Party met on April 23 in Charleston, South Carolina in hopes of ironing out their differences. Although Douglas was the party favorite, his loyalty to popular sovereignty above and beyond the Dred Scott decision did not sit well with the southern constituency. In an attempt to win back his southern critics, Douglas had pushed a sedition law through Congress, suppressing all declarations against slavery in public or private.
But such measures were a sidestep from the true controversy, which revolved around the place of slavery in the territories. And in this, Douglas and his allies refused to budge. After the northern wing of the party defeated a motion to protect slavery in the territories, the threat of an actual split became a reality. The delegates from Alabama led a dramatic exodus out of the convention, followed by representatives from Mississippi, Louisiana, South Carolina, Florida, Texas and scattered other states.