How many presidential debates are there?

September 26, 2008: Video: Obama/McCain debate from the University of Mississippi, Oxford, MS October 2, 2008: (Tickets) Vice Presidential debate, Washington University, St. Louis, MO October 7, 2008: (Tickets) Presidential debate in a town hall format, Belmont University, Nashville, TN October 15, 2008: (Tickets) Presidential debate with domestic policy focus, Hofstra University, Hempstead, NY