The Gulf, Mobile and Ohio Railroad ran an overnight Chicago-St. Louis train called the Midnight Special, which left Chicago at about midnight. The song "Midnight Special" recalls the passage of the train past the Joliet state prison, which made the prisoners wish they were on that train.
As far as Chicago-Florida trains are concerned, my March 1964 Official Guide shows a 10:30 p.m. departure from Dearborn Station for the Dixie Flyer on the C&EI (and eventually L&N and ACL) for Jacksonville.
There's a song called "Dixie Flyer," too -- but Randy Newman either used some poetic license or was misremembering (the song is autobiographical) and gave the name to a Los Angeles-to-New Orleans train. (
YouTube link to hear the song)
I am going to surprise everybody and give this a slight chance of maybe.
How so?
It is like this, the Chicago and Eastern Illinois ferried the "real" Dixie Flyer on the Chicago to Evansville portion of its run--and then Evansville to Nashville on the Louisville and Nashville. There were other trains which went from Chicago to Nashville to New Orleans on that route.
It is possible, though I do not recall seeing anything about it, there may have been timetables where the Dixie Flyer to Florida ran combined with some other train as far as Nashville from Chicago to New Orleans.
Some trains did that, almost even up to the last.Such as the famed Humming Bird and Georgian streamliners.
It would mean the passsenger might see the name of two trains running combined, one the Dixie Flyer and the other whatever name it might have been, to NOL. And mistakenly thought his train was the Dixie Flyer. But this is all just conjecture. It is easy for passengers to mistake the name of the train they rode.
At one time or another I have probably seen the names of almost all trains from about 1945 forward and I would certainly have noticed this duplication of one of the trains my parents grew up riding.
So, my best bet is that it is a wholly made up title...but I give it some chance of confusion between two trains running combined as one.