Americans usually do one of three things when they are able to join a party. They join the largest party, they join a party they think is comparable to the party they belong to in Real Life, or they don't join any party whatsoever. To the people in that last category, you need to get off your @$$ and join a party.
While I know that there is no good way to gauge the membership of political parties, if everyone would join/stay in one party there would be a better estimate. If you do not join a party, all you are doing is depriving yourself of the extra experience point that you would get for voting in the party president election; as well as depriving yourself of the ability to delve much further into politics, such as running for congress or possibly the presidency. The fact is, that this game becomes so much more fun if you actually communicate with people. At its roots this game is a bit simplistic, but due to the inovation and thinking of some citizens, it has become the geopolitical/busines/life simulation that we have all come to know and love.
If you are one of those people who log on to Erepublik every day, and you are still wondering why you don't have any friends; try joining a party. It only took a few hundred millenia for the evolutionary process to develop the ability for humans to speak, why not start communicating with the E-World.
If you are looking for a suggestion, may I suggest the America's Advancement Party. Granted, I am a bit biased on that as I am a member of that party (who is running for congress in Colorado BTW). That fact aside, there are good people in that party who are sure to be able to spice up your E-life.
So, Two Clickers, Non Comms, Slackers, Noobs and any other group or person who does not have a good reason for not joining a party:
Get off your @$$ and join a party!