Hints for Meeting Your Public Officials

Think about what you're going to say in advance; if part of a group, decide who will say what, and remember to budget your time. Be sure to ask for their support for your position!
Introduce your group, describe the organization you represent, and point out its connection to the official's constituency.
Understand that your time will be limited. Be on time, but be polite if the official is not - or if you are asked to meet with their staff. (Relationships with staff are worth cultivating, and they often will be helpful.)
Don't overstate your case, or try to 'bluff' answers to questions --- it is always acceptable to say "I don't have that information (don't know that answer) but I'll get it for you." (Be sure to follow-up!)
If an official agrees with your position - excellent. If not, understand that you must be able to disagree "agreeably" --- always keep a professional manner and tone. (Remember this when planning a meeting with a potential opponent - don't include a zealot.)
Thank the official for their time and consideration. Offer to keep them informed of your activities - and do so. Build the acquaintance to a relationship.