Abraham Lincoln won his first elected office, a seat in the Illinois House of Representatives, in 1834, the same year Joseph Duncan of Jacksonville was elected governor of Illinois. Duncan's home became the official governor's residence from 1835 to 1838 and is the only remaining governor's mansion in Illinois other than the one in Springfield. Lincoln and Duncan both belonged to the Whig Party, formed in opposition to President Andrew Jackson's policies and the Democratic Party, and the Whigs supported a strong central government, a national bank, a protective tariff, and internal improvements at government expense. In 1840, Lincoln and Duncan spent considerable time together in southern Illinois promoting Whig principles, and poll book records show that Lincoln voted for Duncan both times he sought the governorship, although Duncan was defeated in 1842 in his second bid, the only political defeat of his career. Construction of the Duncan Mansion began in 1833, and it became one of the earliest and grandest homes on the Illinois prairie, where Joseph Duncan and his wife Elizabeth hosted figures including Daniel Webster, General John J. Hardin, and Stephen Douglas. From 1865 to 1875, the mansion housed an experimental state school for the education of "feeble-minded children," and in 1920 the Rev. James Caldwell Chapter of the Daughters of the American Revolution purchased it and has maintained it ever since. Joseph Duncan was noted for heroic service in the War of 1812, service as a state senator and United States Representative from 1827 to 1834, and his term as Illinois's sixth governor. He was also a strong advocate for free public education and helped pass federal and state legislation for the construction of the Illinois-Michigan Canal connecting Lake Michigan and the Mississippi. Joseph met Elizabeth Caldwell Smith in 1828 at a dinner hosted by President John Q. Adams, and in her diary Mrs. Duncan recalled the evening and described her crimson-silk dress, thread-lace ruffle, embroidered-silk stockings, satin slippers, and high carved tortoise-shell comb.