Taft. A 1986 survey of historians ranked Clay as the greatest senator in U.S. history, while a 2006 survey of historians ranked Clay as the 31st-most influential American of all time. A 1998 poll of historians ranked Clay as the most qualified unsuccessful major party presidential nominee in U.S. history. In 2015, political scientist Michael G. Miller and historian Ken Owen ranked Clay as one of the four most influential American politicians who never served as president, alongside Alexander Hamilton, William Jennings Bryan, and John C. Calhoun. Noting Clay's influence over the United States in the last three decades of his life, biographer James Klotter writes that "perhaps posterity should no longer call it the Jacksonian Era ... and instead term it the Clay Era." Monuments and memorials Many monuments, memorials, and even high schools have been erected and named in honor of Clay. Sixteen counties, one each in Alabama, Florida, Georgia, Illinois, Indiana, Kansas, Kentucky, Minnesota, Mississippi, Missouri, Nebraska, North Carolina, South Dakota, Tennessee, Texas, and West Virginia, are named for Clay. Communities named for Clay include Clay, Kentucky, Claysville, Alabama and Claysville, Pennsylvania. The United States Navy named a submarine, the , in his honor. Several statues honor Clay, including one of Kentucky's two statues in the National Statuary Hall Collection. Clay's estate of Ashland is a National Historic Landmark. The Decatur House, Clay's home in Washington, D.C. during his tenure as secretary of state, is also a National Historic Landmark. Due to his involvement in the American Colonization Society, a town in the newly formed Liberia in West Africa was named Clay-Ashland after Henry Clay and to where the freed slaves from Kentucky emigrated. See also An Act for the Admission of the State of California List of slave owners List of United States Congress members who died in office (1790–1899) Notes References Works cited Further reading Secondary sources Klotter, James C. Henry Clay: The Man Who Would Be President (Oxford UP, 2018) online review Lévai, Csaba. "Henry Clay and Lajos Kossuth’s Visit in the United States, 1851–1852." Eger Journal of American Studies Vol. 13: 219–241 online. Morgan, William G. “Henry Clay’s Biographers and the ‘Corrupt Bargain’ Charge.” Register of the Kentucky Historical Society 66#3 (1968), pp. 242–58. online Morgan, William G. “John Quincy Adams Versus Andrew Jackson: Their Biographers And The ‘Corrupt Bargain’ Charge.” Tennessee Historical Quarterly 26#1 (1967), pp. 43–58. online Patrick, Andrew P. "Hemp