Washington - Isupportthismessage.com on Monday launched its grassroots site aimed at providing feedback to messages being sent by politicians and interest groups. The site, founded by a trio of dot-com veterans and political insiders, will post video, audio and print messages from interest groups and politicians, and allow users to comment on and post their own multimedia messages in response. It also displays the percentages of site readers who support and oppose individual messages. Isupportthismessage.com will then provide hard copy and electronic reports to interest groups, Congressional offices and candidates.