Should I ask a Part-Time professor?

[MissMoneyJenny]

I am aware that normally Part-Time profesors don't do recommendation letters, but I am in a seminar right now and the professor for it really is my best bet for a good recommendation letter other than the professor who runs the lab I volunteer at. Other than these two I don't really have a good relationships with professors and the best I'll be able to get from recommendations from them is that I got a good mark in their class and that I can write good papers.

I know it's a bit of a shot in the dark, but should I ask just in case?

[emmm]

One of my letters was from a part-timer (without a PhD, even!). I got in to a great program, but some of the other programs I applied to probably didn't think much of ANY of my letter writers.

[moody]

It depends what is meant here by "part-time professor." Do they have a PhD? If yes, then this is likely fine, given that you think this is your best chance for a strong letter. Otherwise I would avoid asking this person - committee members want to hear from people who know what it takes to succeed in a PhD program, and it is difficult to speak convincingly about this if a person does not have a PhD him/herself. (Caveat - if you are applying to a professional masters program of some sort this is less important.)