Some good resources for teaching the elections and the process:
The Living Room Candidate: Online exhibit from the Musuem of the Moving Image. Presidential campaign commercials from 1952-2008, along with links to resources and lesson plans. Also includes a link to 40 different ads from the current campaign. Very cool!
PBS Vote 2008: Multimedia resources to "discover the power of social media and promote students' civic engagement." Includes both elementary and secondary lesson plans.
C-Span Classroom: Great site with downloadable video archives of political speeches and interviews. TONS of free resources.
Factchecked.org: Educational version of factcheck.org, a site that researches/verifies/debunks the candidates' political statements.