About 10 entities signed an open letter dated February 16 to US legislators imploring them to back the electric vehicle maker and its factory-to-customer distribution sales model. In addition to groups like the Consumer Federation of America and Institute for Justice, both the Koch's uber-conservative Americans for Prosperity and the ever-green Sierra Club are on that docket, with the former supporting the cause out of a desire for a more free market and the latter on board because of emissions-free transportation. Those entities all decry the traditional distribution system that they say restrains innovation and does not "rest on a legitimate public policy basis."
Tesla has long been battling a number of states for the right to sell direct to consumers, with Michigan, New Jersey and Texas among the company's most hardcore adversaries. More recently, Connecticut and Arizona have made moves to legalize direct-to-customer sales from Tesla. You can read a copy of the advocacy letter (PDF).