But the data indicates that Monday’s face-off may well have been the most-watched debate in American history.

CNN and other cable news channels saw big increases over past election years. So did some of the broadcast networks.

The early Nielsen data confirms that viewership stayed high the entire time. Contrary to some speculation, there was not a big drop-off after the first hour of the 98-minute debate.

The event was carried on more than a dozen TV channels, some big and some small.