dvertisers paid a premium for airtime during the first Republican presidential debate on Fox News, but it looks like they’ll be getting a major discount during round two on Wednesday night.Semafor reviewed the rates the network shared with one prospective ad buyer for both the first and second GOP primary debates. For the first debate, the cost of a single 30-second spot topped $495,000. But the same 30-second spot during Wednesday night’s contest would cost just over $200,000.Another ad buyer did not share the rates for ads running during the first debate, but confirmed that Fox was charging $225,000 for...