If you've never checked out C-SPAN's website for teachers, you really should.
C-SPAN in the Classroom offers materials for Classroom Civics and Social Studies Teachers. With elections this fall it's a good idea to start collecting materials now.
No, I'm not being paid by C-SPAN, but I did work there for a year, a long time ago.
Great people. They'll help you find video you can use in your classroom too. Check it out.
http://www.c-spanclassroom.org/