What year is your Elentra, stick/auto, 2/4 door and how much does your safe weigh? I think both the 2 door and 4 door are alittle under-rated on towing capacities.
My 2013 Subaru Outback is rated at 2700lbs with 173hp 4cylinder engine CVT in USA, in Australia its more like 3500.
The JK 4 Door can tow more than 3500lbs just on engine and wheelbase alone, as long as the hitch you installed can manage that weight or more...
The major mountains in Colorado could prove challenging, especially if you drive the Ike Gauntlet, so any major sustained elevation, get in the slow lane and don't push it but as has been mentioned you got the granny gears and they aren't ideal for towing, though many pickups come with these kind of gears.
I had a 2011 Chevrolet Silverado with tow pack, 3.42 gears, 315hp, rated to tow 9800lbs, but I would never tow that much with that setup.
So back to your question from a frame, engine, wheelbase standpoint I am sure it can do it, body on frame not unibody like my outback, the gears aren't ideal but you just have to slow down for grades and it can be done, assuming the Elentra is around 2500lbs, your safe if its 1000lbs along with the dolly/trailer add on, you can figure out where you are going to be over/under.