Can alligators survive an Ohio winter?

It depends. Alligators are far hardier than their crocodile cousins and hardier than people think. They can burrow into a riverbank and go into what is nearly a form of hybernation. At the northern end of their distribution range it gets pretty cold (seriously, southern Virginia and northern North Carolina can get pretty darn cold in the winter, well below freezing). It would not be impossible for an alligator to survive in Ohio, particularly in the Southern part of the State (particularly the Ohio River which rarely freezes). Also, some peole have postulated the theory that some of the alligators that have been captured in Southern Ohio (Cincinnati, etc) actually may not have been released pets but rather alligators that came up the Ohio River from the Mississippi River in search of food and territory. In addition to the alligators's natural hardiness which can help it to survive an Ohio winter, if an alligator finds a warm-water source (such as outlet from a power plant) then there is absolutely no reason that it can't survive. To sum it up, aligators are much hardier than most people realize, you only have to dig into the earth a few feet for a constant temperature in the 50's (even in winter), and Southern Ohio's climate is milder than most people thin with several warm days breaking it up (particularly in the souther part of the State) and not that dissimilar to the climate in the northern range of the alligator, and the Ohio River and its contributaries (at least where they run into the Ohio River) rarely completely freeze over. So yes, alligators can survive an Ohio winter.