ID this WWII (I think) era plane?

There’s a municipal airport (San Martin, CA) that I pass by on the highway often, and there’s been a pretty big aircraft parked there for several years, and I wonder what it is. I managed to dig up this picture of it, but no other information about it. Besides what you see, the plane also has what looks to me from a distance like a tail-gunner’s bubble in the back between the two vertical stabilizers. I’m guessing a WWII bomber of some sort? Anybody know?

http://en.wikipedia.org/wiki/B-25_Mitchell

I initially thought it was a B-24 Liberator, but it seems to only have two engines not four.

2007 article from the Morgan Hill Times: Helping History Soar

Wow, awesome, thanks!! You guys rock!