David Duke, a former grand wizard of the Ku Klux Klan, overcame two last-minute challenges and was sworn into the Louisiana Legislature. Duke took the oath of office after surviving a lawsuit and an attempt by a lawmaker to deny him his House seat in a dispute over whether Duke was a legal resident of his suburban New Orleans district, which is 99.6% white. Duke, 38, smiled and waved before Speaker Jim Dimos administered the oath, which followed an attempt by Rep. Odon Bacque to have the House investigate if Duke lived in the Metairie district a year as required by law. Opponents have said Duke lives a couple of blocks outside the district. Earlier, John Treen, a Metairie home builder who was defeated in Saturday's election, lost a last-minute lawsuit in state court to block Duke from being seated for not meeting the residency requirement.