[Re: Abner's Wife]
Since he moved to at least three states, a timeline would be helpful. Where was he and when could he have married? It would help if you fill in his location in the timeline for each census period, at least.
A census history, children's birthplaces, WWI Draft records, etc. would help in creating this timeline.

Did he have any children in the census? Their death cert may list their mother's maiden name and place of birth.

Also, was he listed with a wife in any of the census records? That would give you a first name, approximate age (birthyear) and place of birth for his wife.

The 1930 census gives the place of birth, marital status, children, wife's place of birth, and age(s) when first married.

Your timeline should show where he could have been at that age - giving you a first place to look for a marriage record. Of course, there is a possibility that the census records show no wife. Also, he could not have been married when he registered for the draft and could have no known children. In this case, you will have to search more modern records (after 1930).

I would start with looking for a Kansas marriage record.
Good luck in your research.