The John E Chamberlin from the 46th was 13/14 years old when he enlisted in 1863 and died in Kansas in 1879. I cannot find any connection to Virginia, his mother was originally from Maryland and father from Pennsylvania. Maybe there was an aunt or uncle who made it to Virginia and he sent a CDV to them.
The jackets are similar, though those are the only two pictures that may be found online of soldier from the 46th.
According to Todd's, the regiment were issued blue semi-zouave jackets with bright blue trousers 1863-1865.
I think you have your man, though the Virginia connection is a puzzle. The hat could simply be a late war or even post war depending upon time taken. He would have been 16 to 17 upon his mustering out. He looks quite stout and most likely fooled the recruiters.
Are there any back marks from the photographer studio?