When advocating for a deposit law, don't go it alone! Enlisting the support and assistance of even a few others can make a huge difference in your campaign. Think: signatures on a petition, volunteers to work at rallies, more voices to spread the word...there's strength in numbers.
It will be relatively easy to find groups who are willing to sign petitions endorsing a bottle bill or join a coalition (See the NYBBBB list of endorsers for an example). Getting groups who support deposits in theory to actually "invest" in the campaign effort will be more difficult , and getting groups “invested” is key to a winning campaign. The sooner groups get involved the better.
One way to both get the attention of potential citizen supporters as well as to help your coalition spread the word to legislators and others, is an online advocacy service. There are several of these. You might find the Network for Good's Online Advocacy pages helpful in finding one that works for you. Be warned, however, that online communications are quite easy to ignore, and, if you have the time and resources, you should try to get in touch with people in a more personal way.
The New York Public Interest Group has succeeded in bringing hundreds of organizations, local governments (See sample municipal resolution) and businesses into their Bigger Better Bottle Bill Campaign and has managed to get a dozen or more groups to devote staff time and resources to the campaign. Visit the links below for examples from the Bigger Better Bottle Bill campaign.