Yeah, it's over. I actually think Sanders might have a better shot at Oklahoma than Massachusetts at this point.
Oklahoma will be hilarious. I wouldn't be surprised if Sanders wins by 10 points, if only because there are going to be a lot of registered Democrats who will attempt to vote for Trump on Tuesday, discover that they cannot and then vote for the anti-Hillary candidate.
Note: I'm not saying this out of thin air; voting registration figures in southeastern Oklahoma are still incredibly lopsided, which is bad for Hillary and Trump. For this reason, I expect Cruz to win Oklahoma as well.