She would have to be an intelligent career woman and there would have to be strict understandings up front about dealing with the kids. Also she would have to be financially responsible and interested in her kids' education. I am not raising some Bebe's kids. I wouldn't date the random average chick that was looking for a come up with her kid but an Angela Alsobrooks or Jericka Duncan type would be fine.
That being said, not being able to discipline her kids is more of a deal breaker for marrying her than the fact she is a single mom. If they are young (like Kamala's sister Maya when she started dating her husband) it can be more adaptive. Otherwise you aren't their dad and they may not respect you. I can't deal with kids you can't discipline.