This sounds like a job for Derb, but a reader writes in to criticize the methodology behind the article that inspired this post:

The rankings in the article were based on the number of viewers who got all three questions right, but you get a different ranking if you simply add up the percentage of people getting all or some of the right answers. Adding up the percentages (I was too lazy to divide by three to get comparative percentages, but the resulting ranking would be the same) you get:
1. Hannity & Colmes: 206
2. NPR: 202
3. New Yorker /Atlantic: 201
4. Rush Limbaugh: 195
5. Colbert: 187
6. O’Reilly: 171
7. News Hour: 165
8. C-Span: 157
9. Daily Show: 149
10. CNN 136
11. Letterman/Leno: 124
12. National Enquirer: 98
By this ranking, conservative-orientated shows rank 1, 4, and 6 out of 12, and the lowest conservative show (O’Reilly) is well above the Daily Show and CNN. It’s interesting that the original article chose a method of ranking that put the liberal outlets on top.