I would vote for the former. That said, I wouldn't allow that to preclude me voicing opposition to the 20%.
Myself, I stick with someone of character whom I didn't agree with on all issues, rather than going with someone who mouths platitudes I agree with but has no character.
Ideally, the person has character AND agrees on all the issues. I'm not sure that person exists. ;-)
Continuing my thought, nor would I consider others who mention that 20% to be disloyal. But, to each their own.