New York (CNN Business) If Democrats were banking on massive viewership of former Special Counsel Robert Mueller's televised testimony, they're feeling broke today.

The Mueller hearings had a loyal audience, but they didn't break any ratings records. Not by a long shot.

Nielsen NLSN Preliminaryratings totals — which are subject to adjustment — show an average of 13 million viewers across six major networks Wednesday.

This is an average of the audience that was watching at home on TV throughout the two hearings, which together lasted a total of seven hours. Not everyone watched the whole time, so the total audience for the event, known as "reach" in TV lingo, was much higher.

Not everyone watched on TV, either. Some tuned in to the hearings on radio, social media sites and streaming services, and those consumers are not counted in the Nielsen data, which includes ABC, NBC, CBS, CNN, MSNBC, and Fox News.

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