That would be cool. Or a Wrangler with the same set up. A smaller battery could be used and rely on an efficient engine to run the generator.
Wrangler is Jeep though?
You'd probably want a larger battery though than a Volt to provide for the power needs torque wise when towing stuff.
Stupidly, the one hybrid truck produced to date
disabled the hybrid systems completely when in towing mode. Meaning that the electric motors weren't helping get the load started.