Where does Missouri fit?

[muon2]

I'd agree with Opebo that MO splits into thirds. However, I drive across the northern half of MO frequently, so I'd expand the Plains area beyond his description. In the northeast I'd extend the St Louis area all the way up through Hannibal to IA and over to Kirksville.

The KC corner extends south most of the way along the KS border, stopping north of Joplin, but staying west of the Truman reservoir. In the north the KC area extend a little east of the I-5 corridor, to include Chillicothe.

That leaves Little Dixie north of Columbia with the Ozark Plateau in the south to make up the Southern-leaning region. However, my drives make me think that Little Dixie is getting more Plains and less Dixie as time goes on. As an aside I'd put the Bootheel in its own category, still southern, but more like the rest of the Mississippi Delta than like the hill country that defines the Ozark region.

[muon2]

Iowa and Missouri are very different.  I'm originally from Southern Iowa, where people speak with a flat accent, but when I was in Northern Missouri, people definitely had a twang.

But it's not a southern twang. It's the same sound you'd hear in central IL or IN as well as in KC. The conservatism there is more like KS than like AR. BTW, are you from SW or SE IA?

[muon2]

Could it be a religious divide?

This is the only really southern aspect of northern MO. The state was part of the split that formed the Southern Baptist Convention, and the denomination remains strong right up to, but not across the IA border.

[muon2]

I'd be careful to read so much into the religion maps. If you take that logic too far then KS should vote like OH. The regions with Baptists on the religion map mostly indicate where the denomination split in the 1840s over slavery. The rural/urban and old-suburban/exurban divides are more important in a state like MO.