Redrum,
It definitely would be to your advantage to get a letter of recommendation from someone who held a prestiguous position as the presidency for the California board of pharmacy. However, you have to ask yourself whether you will have the opportunity to work with this guy close enough where he can write a strong, detailed letter for you. If he is always busy with other concerns and forgets about you right after your first day of work, then his letter of recommendation might not be what you hoped for. Remember also that when he writes his letter, he, more than likely, won't be pointing out that he was the former president the California board of pharmacy, nor will most remember that he served that position (heck, I don't even know who's the mayor of my home city is). I'm sure he has an important position now, since he's doing the hiring, and this will definitely catch the eyes of the admission committe when they first scan the letters.
What is most important is that the person writing the letter of recommendation takes the job seriously, fully knowing that someone's future is on the line, and does a good job. His title will only peak the interest of the readers, but the content and the specific examples your supervisor can provide will determine whether you have a good letter of recommendation. To this end, provide your intended recommneder with a CV and coverletter as well as a conversation emphasizing how seriously the admission committee takes the letter of recommendations.
