It was recently found that when the FCC (or some other US federal govt. agency) has a request for comments, they're only compelled to seriously consider the in-depth, intelligent comments. In practice, this means that form-letters done via the EFF website etc. are tossed out, while lawyer-produced walls of text that read like Congressional legal pronouncements get serious consideration. Almost always, the latter are produced by big businesses with lots of money to spend on lawyers to ensure the decision goes in the direction of greater profits for themselves.
The only way to undermine this is for organizations like the EFF, and individuals, to gather and present as much easily-digestible data as possible and edit and refine their message until it's intelligible and palatable to a politician. Mindless ranting is immediately dismissed as uninformed. Probably only a dozen or so of these 1.7 million messages will actually be read by a decision-maker.
Fax is the best medium to contact your agencies with, as it tends to be printed and read by a human, rather than a keyword-search-delete-all like can be done for email ("delete all emails containing superlatives"). Also, 1.7 million sounds alot bigger when pushcarts full of paper can be wheeled into their office, rather than the messages easily fitting on a disc or flash drive. I presume they don't tend to auto-OCR faxes.