Okay, I've decided I'm going to take this directly to CTA, despite the trouble I've had asking them about their vehicles in the past. Although at this point, I'm leaning towards a TMC RTS.

http://www.chicagobus.org/bus/4400


UPDATE: CTA still hasn't replied after all this time.

I thought it was the 6000 series at first, but then I realized it's probably the 4000. Also, that windshield is a little to slanted to be a Flxible Metro.

If it is a 6000-series number, wouldn't it be a Flxible Metro?

http://www.chicagobus.org/bus/6000

I'm pretty much done with adding vehicles to the 2006 indie flick The Architect for now, but one vehicle that has stumped me has been this Chicago Transit Authority bus I can't identify:
http://img196.imageshack.us/gal.php?g=architectunknownctabus1.jpg



I know it's just a background vehicle, but it just stands out too much to ignore. I also thought the fleet number might help identify it, but no such luck, So until I have a clear ID of the make and model, I'm leaving it on the main page... unless somebody here can identify it.