President-elect Barack Obama thanks Illinois residents as he resigns from Senate . The president will be sworn in on January 20 at the U.S. Capitol and take office Jan. 20. Jesse Jackson Jr. , Tammy Duckworth among names mentioned to fill vacant seat .
President-elect Barack Obama thanks Illinois residents as he resigns from Senate . In letter , Obama recalled moving to Illinois , people he met during his U.S. Senate run . Jesse Jackson Jr. , Tammy Duckworth among names mentioned to fill vacant seat .