Do you use custom voting buttons? While you can't edit the list of choices, you can prevent the need to retype your choices by saving a template or publishing a custom form after entering the choices and completely other information that will remain the same on each message.

Remember - if you use Word as your editor, you need to use the Outlook editor to save a template. You can choose it from the Actions, New Message Using menu. Select the item for Microsoft Outlook ([default format]) - it should be just under the stationery options.

You can either save it as a template or publish it as a form. See http://www.outlook-tips.net/search/search.pl?Realm=Outlook-Tips&Terms=templatess  for links to previous tips about using templates and forms.