Benson does not mention (gee, I wonder why?) two other possible factors in the less-positive coverage for Romney coverage in the last days of the campaign:
1.) Professional journalists, trained in assessment of real-world factual data, had little trouble recognizing that when it came to the Benghazi story, conservatives were trying very hard to amplify it into a major scandal when there wasn't enough "there there" to justify the characterization.
2.) When Romney doubled down on the obvious lie about jeep jobs moving to China, it underlined what a prevaricating sack of you-know-what he'd been throughout his campaign.