I think they do. To test the theory, I looked the Survey USA sampling -- asking 1000 voters per state who won the debate. But my interest isn't in who won, but in who watched.
The top five states were Colorado, California, Oregon, Florida, and Pennsylvania. In each of those states, more than 50% of the voters polled watched the entire debate. (up to about 55% in Colorado.)
The bottom five ranged from Illinois (45%), through Arkansas, Kentucky and Texas to Oklahoma (42%).
A slightly expanded version of the argument is available at deadlyearnest.blogspot.com
The point I draw from all this, (aside from the fact that the south is filled with ignorant, apathetic bumbleheads who can't be bothered to watch the most important 90 minutes of scheduled television in our recent history) is that swing state voters are more likely to tune in than the partisans of states where there is less diversity of opinion. This seems to run counter to the CW that the partisans watch to cheer their candidates on. If so, New York, Illinois and Texas should have been on top.