Accepting the nomination, Lincoln delivered his House Divided Speech, drawing on Mark 3:25, "A house divided against itself cannot stand. I believe this government cannot endure permanently half slave and half free. I do not expect the Union to be dissolved—I do not expect the house to fall—but I do expect it will cease to be divided. It will become all one thing, or all the other." The speech created an evocative image of the danger of disunion. The stage was then set for the campaign for statewide election of the Illinois legislature which would, in turn, select Lincoln or Douglas. When informed of Lincoln's nomination, Douglas stated, "[Lincoln] is the strong man of the party ... and if I beat him, my victory will be hardly won."The Senate campaign featured seven debates, the most famous political debates in American history. The principals stood in stark contrast both physically and politically. Lincoln warned that "The Slave Power" was threatening the values of republicanism, and accused Douglas of distorting the values of the Founding Fathers that all men are created equal, while Douglas emphasized his Freeport Doctrine, that local settlers were free to choose whether to allow slavery, and accused Lincoln of having joined the abolitionists. The debates had an atmosphere of a prize fight and drew crowds in the thousands. Lincoln's argument was rooted in morality. He claimed that Douglas represented a conspiracy to extend slavery to free states. Douglas's argument was legal, claiming that Lincoln was defying the authority of the U.S. Supreme Court and the Dred Scott decision.Though the Republican legislative candidates won more popular votes, the Democrats won more seats, and the legislature re-elected Douglas. Lincoln's articulation of the issues gave him a national political presence. In May 1859, Lincoln purchased the Illinois Staats-Anzeiger, a German-language newspaper that was consistently supportive; most of the state's 130,000 German Americans voted Democratic but the German-language paper mobilized Republican support. In the aftermath of the 1858 election, newspapers frequently mentioned Lincoln as a potential Republican presidential candidate, rivaled by William H. Seward, Salmon P. Chase, Edward Bates, and Simon Cameron. While Lincoln was popular in the Midwest, he lacked support in the Northeast, and was unsure whether to seek the office. In January 1860, Lincoln told a group of political allies that he would accept the nomination if offered, and in the following months several local papers endorsed his candidacy.On February 27, 1860, New York party leaders invited Lincoln to give a speech at Cooper Union to a group of powerful Republicans. Lincoln argued that the Founding Fathers had little use for popular sovereignty and had repeatedly sought to restrict slavery. Lincoln insisted that morality required opposition to slavery, and rejected any "groping for some middle ground between the right and the wrong". Despite his inelegant appearance—many in the audience thought him awkward and even ugly—Lincoln demonstrated intellectual leadership that brought him  into contention. Journalist Noah Brooks reported, "No man ever before made such an impression on his first appeal to a New York audience."Historian David Herbert Donald described the speech as a "superb political move for an unannounced candidate, to appear in one rival's (Seward) own state at an event sponsored by the second rival's (Chase) loyalists, while not mentioning either by name during its delivery". In response to an inquiry about his ambitions, Lincoln said, "The taste is in my mouth a little."

Question: What did he expect not to be dissolved?
Answer: Union