oversampling repubs, by their own admission
As stated earlier, CNN's normal viewership, per a Pew poll of 2009, is 51% Dem, 18% GOP, 27% independent. Do you actually think that is a breakdown of the country at large?
31% Dem ad 33% Republican is closer to what the makeup of this country is, politically speaking.
When we talk about oversampling, we are talking about breakdowns via state and/or by the country, overall, not CNN's normal viewership.