yes, this can be done with no sweat. Many guys, myself included, paired their ATP ride with a type ride. In that case it is the same PTS, so there are no extra maneuvers or oral questions. the only prob with doing the commercial this way is that there may be some things that you'll have to do for the commercial PTS that wouldn't otherwise be required to do on the type ride. Chandelles, lazy 8s, right off the top of my head.
For me it would depend a lot on the type rating you are talking about. Is it a jet? Much higher performance than what you've been flying? Will the training be done in a sim? You may be setting yourself up for a great deal of added difficulty in doing commercial pilot maneuvers in an airplane that you'll be barely hanging on to to begin with. And flying a sim really is a learning curve all on its own. Those things are bigger issues to me if I were considering a check ride in this way.
What are you coming from/getting in to?