Door Doesn't Want to Close All the Way

Having a problem closing my driver's door on my 65 Dart. I've tried adjusting the striker plate and the hinges, no change. I'm thinking its the latch but that seems to be working. When I close my door, it latches but has about a 1/2 inch gap. It will close fully if I push on it but then it pops open a half inch. The latch operates with the button to open. Any ideas? It doesn't seem like anything is obstructing it.
I was having a similar problem on my 70 Duster, it turned out the rubber seal that goes around the front of the door was loose and was wedging against the front of the door jamb. Probably not the same problem, but I thought I would throw that out there.