I recently bought a 2008 Pacifica Touring. The floorboard is soaked on the drivers side. Thought at first it was from tracking snow in, but it doesn't seem to be drying out. Can anyone tell me what the problem could be??

 

Could be a leak around the windshield or cowl area some where. Could be a heater core leak but those usually are on the passenger side. Could be a plugged drain for the sunroof or a plugged cowl condensate drain.

You can't leave that wetness there or it'll rust out the floor pan in a hurry and/or turn into a science experiment. Buy or borrow a wet/dry shop vac and suck out as much of the moisture as you can. Then find a dry and secure place to park the car like inside a garage and put a fan in there, preferably with the car windows open and blow as much air through there as you can. It will likely take a few days to dry it out. If you're driving it in the meantime, run the heater full blast and open a window to move a lot of warm air over the carpet.
Once the weather warms up you might want to try to hunt down the leak using a hose but that can be quite difficult as the water might be coming in at a very different location from where it's winding up.
If you have a sunroof, make sure the drains are operating properly. Make sure the condensate drain through the firewall is clear as well.