Your implicit assumption, that leftist-controlled TV news will be the only source of information, is, IMO, incorrect. It is already only a vestige of its former self.
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The only source, no.
The one that useful idiots "rely" upon, yes.
Foxnews, the web, FR, and other alternative news sources reach only the interested, the involved and the intelligent. The voting masses still rely primarily upon the boob tube.
HAPPY NEW YEAR!!......FRegards