Yes Mr Dyess, they will if they are a real publisher (Uncle Jim will probably go off on POD's and the like shortly). If they are a small publisher, however, they may only have one publicist covering the 10 or 20 titles they release each year. So the professional marketing people may not get to it until the project is on their horizon. Certainly a publisher will not have publicists working up a marketing plan for every proposal that comes across the transom.Jason M. Dyess said:...my wife... has found a few publishers who accept unsolicited submissions but request a marketing proposal. Her question is, "How do you write a marketing proposal for a novel?"
My addendum to her question is, "Should a writer submit to a publisher that wants an untrained person creating their marketing plan? Don't they have people who do that?"
What they are looking for in the proposal is an indication that the prospective author has thought all this through. For nonfiction this is crucial. In many cases the author will be directed to write the material to the market instead of the other way around. In fiction or literary nonfiction that obviously doesn't quite work, but they will still want to know that the author is cognizant of what other books are out there and what sells.
Once the editors and/or agents who screen proposals pick one they find interesting, they will next have to pitch it to the higher ups. At this point it is being evaluated as a business proposition as much as anything else. The acquisitions people will add some of their research and market knowledge, and are trying to convince the decision-makers that the project is going to sell. The more the author does to help this process, the more likely the proposal is to get pitched to the publisher.
For how to write the proposal, including a marketing plan, try your local library. There are entire books on this subject.