From Click Here for Change: Your Guide to the E-Advocacy Revolution (pg 16-17):
A study conducted by the Congressional Management Foundation found that not all tactics for reaching out to legislators carry the same weight and that Internet communications, while easier to accomplish than other approaches, do not necessarily mean less impact. When legislative staffers were asked to rank the impact of different communication methods on the decision making of congressional members, they clearly indicated…that online and offline communications— particularly individualized emails or letters—do indeed have influence.
The study confirmed a principle that the receipt of 50 thoughtful email messageswritten in constituents’ own words would be more effective than 300 identical form messages, even if delivered via postal mail. Moreover, congressional staff overwhelmingly felt that large numbers of email messages, which are easier to organize and respond to, are preferable to an unwieldy onslaught of faxes that are difficult to respond to and consume costly office supplies.
A key message of this study is that a mix of online and offline approaches, which are both targeted and strategic, provide a more robust approach to advocacy than a single approach. The key is to balance activities in the online and offline worlds that reinforce the campaign’s core strategy.