The idea that a 14 year old girl could not (cannot) willingly consent to sexual intercourse did not make its way into the legal code until fairly recently. Inserting the age differential into the codes is even more recent.
Perhaps Wyoming is unique, but in most states if you want to run for office - you file the papers, pay the fees and/or gather enough signatures to get on the ballot. Unless he is filling an appointed seat, he has been previously elected by Wyoming voters - not the party.
I don't know if some here are projecting or reacting to something terrible that happened to someone you love - but nothing I see in the article or have read in the comments thus far supports the ideas of rape or trauma or anything that would “cause” the wife's later suicide.
This was fairly recent, 1986-1990.