In reference to my earlier post to you, I don’t know Missouri’s population dynamics, but in Oregon, 57% of the state’s total population lives in the Portland Metro Area. That’s what explains its disproportional weight, electorally speaking.
I have not checked last census numbers but Kansas City, MO (NOT Kansas City, Kansas) and St. Louis were fairly close in population numbers. Now there are numerous 'burbs' around each of the named cities above. So sometimes here on the Kansas City side there can be conflicting interests on the ballot from county wide versus the Kansas City. These are usually what draws out the unions.
Unions carry a fairly big weight, and they tend to get energized when some particular ballot measure gets put on the ballot...