Cruz is the most likely winner in the end, if not in New Hampshire, where Kasich might actually win. I can actually see this coming down to Cruz (evangelical/Tea Party wing) vs. Kaisch (moderate/blue collar wing) in the end instead. I really think the release of the tape that early would have sunk Trump fast. He was still kinda in flux at that time, his fate by no means secure. The cult wasn't fully formed or devoted to him yet. He was still seen largely as a novelty. A number of things could have caused him to implode and be stopped in its tracks at that time, and I think the tape could certainly do it. His momentum likely would have been killed; the same pastors who ironically sucked off Trump since would have damned him to hell in public, all his GOP opponents would have pounced on him and called him a RINO and Democrat and Bill Clinton 2, etc. He would have been massacred. Hard to believe now, I know, but you gotta try to remember the context of the time was still just totally different.
Outside of Ohio, Kasich had no blue collar appeal. In his competitive governor race in 2010, a decent of amount of the Rust Belty or Appalachian types of places went for his opponent. Additonally, Kasich has supported free trade and is open to amnesty, two positions that would kill any non-Ohio blue collar appeal.