THe starter is grounded when it's mounted to the engine. THere is a ground wire that runs to the engine block. You could check to make sure it is clean and tight.
However, I have another concen. In the old days, Chrysler placed a voltage regulator on the firewall, Cheap and easy to replace. When the Dakota was introduced, the alternator's voltage was regulated through the computer. If I had to guess, I would say that is where the problem is if you checked all of the wiring and it is good.
I've owned Dakotas since 1990. I love them. Had a 90, 92, 98, 00, 07. THey are well built and will run well over 200K if maintained. (My 90, at 60K miles, decided to do what you are explaining. I had to replace the computer. If you get one from a salvage yard, make sure the part number is exactly the same as yours or you'll end up with other trouble.
Let me know if this helps or if you find something different.
Saturday, October 3rd, 2009 AT 9:46 PM