I would imagine that Orrin hatch would not like it, because the LDS Church would be against it. Observe that neither Utah nor Idaho has decriminalized marijuana, even for medical purposes. In other states, the churches oppose legalization. The cops oppose it, sometimes perhaps because they don't want to eliminate police jobs, sometimes because they believe that potheads are more likely to be criminals, which is a self-fulfilling prophesy. There are a LOT of people against decriminalization,and many are self-identified conservatives. You do not see any signs for legalization at Tea Party rallies, either.
I am sure that there are many who have different [positions, but they are in the minority.