Explain Senator Stephen Douglas' attempts at securing a bid for the Presidency

Stephen Douglass was a Democrat elected to the U. S. Senate in 1858. Douglas defeated Abraham Lincoln to obtain his Senate seat. He was a supporter of the idea of popular sovereignty, the belief that the settlers in newly admitted territories should determine whether the area would be slave or free. Douglass received the Democratic nomination for president in 1860. Douglass support of popular sovereignty led to the splintering of the Democratic Party into Northern and Southern factions. Northerners opposed secession while Southerners supported it. The splintering of the party led to their defeat and the election of the Republican Abraham Lincoln in 1860.