According to the .gov, there are about 313 million people in the US. http://www.census.gov/main/www/popclock.html <---refresh this a few times and watch the number rise, lots of screaming babies!
According to the .gov, there are roughly 600 thousand active pilots. http://www.faa.gov/data_research/aviation_data_statistics/civil_airmen_statistics/2010/ <---download table 1 for the relevant data
That means less than 1 in 500 US citizens are pilots, or around 0.2% of the population. When I first divided it out, I though I had missed a decimal point or something.
[hypothetical]
If I were a politician, and I really wanted user fees for example, I wouldn't lose too much sleep over .2% of the voters getting upset about it, at least half of whom probably already don't support me. Oh, I know it's actually slightly more than 0.2% if you count all the aviation related jobs and such, but still... Besides, if you consider all the airline folks that think this is a great idea, then it might actually be less than 0.2%!
[/hypothetical]
So, what group/who is the most effective advocate for us, the little guys (and gals too, although there're only 42 thousand of you, or 0.013%)? EAA...RAF...AOPA...? Where does your money go?
(Edited to tone down the rhetoric of the hypothetical politician in me--don't mean for this to end up in hot air)