Key points are not available for this paper at this time.
Joanne M. Miller, Jon A. Krosnick, News Media Impact on the Ingredients of Presidential Evaluations: Politically Knowledgeable Citizens Are Guided by a Trusted Source, American Journal of Political Science, Vol. 44, No. 2 (Apr., 2000), pp. 301-315
Miller et al. (Sat,) studied this question.