They're playing to the base now, during the primaries.  In doing so, they are willingly giving Democrats ammunition for later.

Once the actualy election campaign starts, they'll play to the centre.  Will the centre buy it?  I'd love to say they won't, but I'm not willing to bet on the memory of the average American voter.

As for the video, apparently the media is left-leaning because they hang out at coffee shops, or some such nonsense.  I couldn't watch after that.  It's just another Christian trying to justify the claims of "liberal media bias" and making stuff up to do so.