If you are asking if you can use a potentioimeter the answer is yes. If you are asking how to connect it check the following FIRST document:
http://usfirst.org/uploadedFiles/Rob...out%281%29.pdf page 5 for this:
How do I connect a potentiometer?
Connect the wiper to the input pin – Top row.
Connect the other two pins to +5 and ground – Middle and bottom rows.
As for the Power required if you use a 1kΩ you would only dispate 144 mW at 12 volts and with a 10kΩ of course 14.4 mW. 1/4 potentiometer would be fine.
A good 10 turn pot works wonderful for positioning feedback.