Ken is dead on...I lived in Marion, IL for a number of years (through high school) and let me tell you, they like to think they are further south then Mississippi. Accent is correct, and they have all the "southern" values that other states below the Mason-Dixon line have. Once you get south of Champaign, things change drastically.
Oh, Molly, sweet, kind, lovable, ranting, raving, suffer-no-fools, Molly, you're making the same mistake many out-of-staters make when thinking of Illinois: You're thinking of Chicago--much to the downstate Illinoisans chagrin and ire.
No the Downstaters will be the first to tell you--with a southern drawl--that Chicago is not the be-all end-all of Illinois. Take a look at a US map. Illinois extends further south than West Virginia and almost as further south than Virginia, Missouri and Kentucky. Drive an hour or two (tho not in "rush" traffic) south (or west even) of Chicago and the area gets quite rural.
Tom's southern Illinois accent was quite correct.
-- Ken from Chicago (where we have no accent, well, except for recent visitors and a few Southsiders)

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