04/01/2008 05:12 am ET Updated May 25, 2011

Extended Primaries Bring Record Ratings To MSNBC, CNN

CNN and MSNBC are wrapping up record first quarters this week, and it's largely thanks to two people: Hillary Clinton and Barack Obama.

Record ratings have led to major ad-sales growth, both of which the networks should be able to ride all the way to the conventions in August, when the highly rated race between Mr. Obama and Ms. Clinton finally comes to an end. But the picture gets cloudy going into this year's upfront sales period, when the networks will be selling inventory for fourth quarter and beyond.

Read more on AdAge