Chabot's opponent ran against him in a more Dem district in 2000, and Chabot won 53-45%. According to Open Secrets, Chabot leads John Cranley with cash-on-hand by nearly 2-to-1 ($1.4 mil to $775k). That's roughly the same percentage Chabot outspent Cranley by in '00. Personally, I don't think Cranley will get more than 45%, perhaps less.
It would be very odd for Chabot to lose now when he has survived much tougher situations in the past. Unless there's a personal scandal of which I am unaware, I would place this race as Likely GOP.