Abraham Lincoln wanted to become president because he was opposed to slavery and wanted to limit the expansion of slave states into the newly acquired Western territories. Lincoln also had a history as a politician, entering the Illinois state legislature as early as the 1830s.
Lincoln's ideals and background are what drove him to become a politician. Because Lincoln grew up poor and was self-educated, he could sympathize with those people who were less fortunate than himself. Lincoln pursued his dream of public service in the Illinois state legislature as a member of the Whig party. In 1847, he joined the U.S. House of Representatives and strongly opposed the U.S. war against Mexico. In 1858, Lincoln made a failed bid for U.S Senate, but his performance in the campaign gave him the recognition necessary for his successful presidential campaign.