excerpt from Conserve Wildlife Foundation of New Jersey 'The eastern cougar was listed as endangered by U.S. Fish and Wildlife Service in 1973, although it was thought to have already been extinct as early as the 1930’s. In 2011, the U.S. Fish and Wildlife Service declared the species extinct. However, in June 2011, a 2-5 year old male cougar was struck and killed by a car in Connecticut. It is believed that this individual roamed over 1,500 miles from the Black Hills region of South Dakota based on DNA evidence. Big cats are very wide-ranging animals that can cover a great deal of distance in a relatively short amount of time as they search for prey, mates, or their own territory.'
Therefore likelyhood of cougar is as close to zero as you can get.
Linx are more northern, they rely on snowcover to overtake prey like rabbits etc.
As to bobcat vs canine, I think TRAP nailed it as well. The symmetry of the print says canine to me. The track is also not fresh so you can't necessarily expect to see claw marks. They could have filled in with light flurries or blowing snow, or melting could have merged them with the rest of the print.
As someone said, tracking is much easier when considering stride and depth of print than size alone. Size changes, track spacing doesn't. A big bobcat is a small coyote, my guess is this would shed light on the situation. Another easy one here is if it goes up a tree it s cat. If you follow the track for an hour and it never leaves the ground, I'd be thinking canince more and more.