Film is offered on demand in Time Warner NYC area and I compared it last night to the DVD. Several odd things: the aspect ratio is more like CinemaScope than VistaVision, and the picture actually looks squished to fit the deeper letterboxing. Also the framing is off: the tops of the sets, the back wall of the sound stage, and lightning equipment is visible in various wide shots during the Dogpatch ensemble scenes, and boom mikes are visible during the scenes in the senator's office.
I don't recall the film looking like this when it was broadcast by TCM several months ago.