State political party – The main Republican or Democratic party organization in each of the 50 states. Each party committee raises money for state and federal candidates. States set their own contribution limits, which vary widely. Many states permit unlimited donations to state parties.

State legislative caucus committee – Fundraising organizations for partisan groups of state legislative candidates. Some states have four separate committees — two each for a state House and state Senate, for example, while others have none.

State account – Holds funds raised by state party and caucus committees under state rules and limits, which differ from state to state. Some states permit unlimited donations to state accounts, while others cap contributions. States also have differing rules on whether corporate or labor union treasury donations are allowed.

Federal account – Each of the 100 Republican and Democratic state party committees maintains a separate account used to raise and spend money on behalf of House, Senate and presidential candidates. These accounts can raise a maximum of $10,000 per individual donor per year; these contributions are known as "hard money." They cannot accept corporate and union treasury funds.

Levin account – A third type of account maintained by state or local party committees that can raise up to $10,000 per person for use in get-out-the-vote campaigns when both state and federal candidates appear on the ballot. Established by the Bipartisan Campaign Reform Act of 2002, but not widely used in 2003.

Hard money – Campaign contributions raised under federal limits. The current limit for contributions to the federal accounts of state parties is $10,000 per calendar year from an individual and $5,000 per calendar year from a political action committee.

Soft money – Campaign contributions raised by national party committees outside federal limits. BCRA banned national parties from raising soft money, much of which in the past was shipped to state parties to pay for advertising campaigns.

Political action committee – An organization registered with either state or federal election authorities to pool and contribute money to candidates and parties. PACs are typically used by corporations, unions and interest groups.