The right hand main elevator stuttered tonight, the door stopped at midpoint and stayed ajar. I waited 15 minutes and we called the elevator from the other floors but it would not respond. I finally went and pushed against the door which then opened fully with an almighty groan. I tried sending it to other floors and called it back several times to 1st floor without any problems. Since it seemed to be operational again we have let patrons ride it without incident for the last hour, but I do think it ought to be reported in the morning to the elevator company just so it is on the record.