I would think you'd be able to...
**I over winter dahlia's in a certain spot here
at the base of my house and I am in a growing zone
so, even if you have your caladiums in a pot,
I would think they'd be easy enough to move into
a slightly heated garage or basement of your house..
Up here, Unless they were in that same exact spot I over winter the dahlia, they wouldn't survive.. but I would think in your growing zone
/area you'd be able to leave them right in the ground...
I am hoping, maybe Jiffy or Alankhart can scoot thru, they're closer to your growing zone
, than I am and would be able to help you alot better than I can...