Absolutely. Thanksgiving week is a busy time. Try going on line and going day by day adding on to see what you can come up with. You might even try working backwards. We did this for Easter a few years ago and managed to piece together 2 weeks. You will have to check quite often and at all different times of the day. My sister and I would both be on the computer at the same time and come up with different availability. Good Luck!
I would call CRO also. I booked my two weeks in December at a partial hookup back in February. Even then online was not showing ANY availability at the campground. When I called, there was no problem getting all of my nights.
I agree that you should call and double check. I called and booked a premium site for the week after Thanksgiving (11/27-12/3) a week or two ago and didn't have any problem getting what I wanted.
I just checked for availabilty arriving on the 20th (nothing on the 18th) and there are partial hook ups showing. You might have to be flexible with your dates but this does seem to be doable!