Counted - STAR (score voting then automatic runoff) voting advocacy group
Fairvote - Ranked Choice Voting (Instant runoff) advocacy group
Democratic Advocacy Groups
The Bridge Alliance - Interesting network of political groups that are trying to increase Democratic participation.
deKieffer, Donald. The Citizens Guide to Lobbying Congress. - Book on how to become a lobbyist.
Demonstrations are rarely effective. Get your members off the streets and into the halls of Congress!
Richan, Willard. Lobbying for Social Change - Another book on how to be an effective lobbyist.
Some interesting quotes:
"Personal commitment to a cause is one of the most underestimated resources in advocacy."
"Lobbying is not a solo activity. Make allies. This may require balancing your agenda against items in someone else's."
Mason, Lilliana. Uncivil Agreement: How Politics Became Our Identity - I haven't read this one yet, but here Lilliana argues that politics is driven less about actual policy and ideology but rather about "identity".
Open Secrets - Tracks PAC spending, political spending, and campaign money.