A congressional caucus is a group of members of the United States Congress that meets to pursue common legislative objectives. Formally, caucuses are formed as congressional member organizations (CMOs) through the United States House of Representatives and the United States Senate and governed under the rules of these chambers. In addition to the term caucus, they are sometimes called conferences (especially Republican ones), coalitions, study groups, task forces, or working groups.[1] Many other countries use the term "parliamentary group"—for example, the Parliament of the United Kingdom has many all-party parliamentary groups.[2]

Party caucuses and conferences in the United States Congress

The largest caucuses are the party caucuses and conferences in the United States Congress, which are the partisan caucuses comprising all members of one house from one party (either the Democrats or the Republicans) in addition to any independent members who may caucus with either party. These are the House Democratic Caucus, House Republican Conference, Senate Democratic Caucus and Senate Republican Conference.

The caucuses meet regularly in closed sessions to set legislative agendas, select committee members and chairs and hold elections to choose various floor leaders. They also oversee the four Hill committees, political party committees that work to elect members of their own party to Congress.

Ideological conferences

Some caucuses are organized political factions with a common ideological orientation:

Most ideological caucuses are confined to the House of Representatives.

Known caucus membership in the House of Representatives[1]
Congress CPC NDC BDC Democrats (in total) Republicans (in total) TG MSP RSC LC HFC Reference
(January 2017)
71 61 18 193 238 50 73[3] 154[4] 8 32 [citation needed]
(January 2016)
70 52 15 188 247 53 68 170 36[citation needed] 39 [5]

^ Total counts may vary as members are not limited to membership in a single caucus. The provided numbers are also those of known members of their respective caucuses and this does not necessarily reflect the true numbers (which can easily be higher).

Racial and ethnic caucuses

Among the most visible caucuses are those composed of members sharing the same race or ethnic group. The most high profile of these represent people of color. These include:

Interest group caucuses

The most common caucuses consist of members united as an interest group. These are often bipartisan (comprising both Democrats and Republicans) and bicameral (comprising both Representatives and Senators). For example, the Congressional Bike Caucus works to promote cycling.


The House Committee on House Administration prescribes certain rules for Congressional Member Organizations (CMOs). Each Congress, CMOs must electronically register with the Committee on House Administration, providing the name of the caucus, a statement of purpose, the CMO officers and the employee designated to work on issues related to the CMO.

The Committee on House Administration rules include:

  • Members of both the House and Senate may participate in CMO, but at least one of the Officers of the CMO must be a Member of the House. The participation of Senators in a CMO does not impact the scope of authorized CMO activities in any regard.
  • CMOs have no separate corporate or legal identity. A CMO is not an employing authority. The Members' Representational Allowance (MRA) may not directly support a CMO as an independent entity. A CMO may not be assigned separate office space.
  • Neither CMOs nor individual Members may accept goods, funds, or services from private organizations or individuals to support the CMO. Members may use personal funds to support the CMO.
  • A member of a CMO may utilize employees (including shared employees) and official resources under the control of the Member to assist the CMO in carrying out its legislative objectives, but no employees may be appointed in the name of a CMO.
  • CMOs may not use the Frank (congressional free mailing privilege), nor may a Member lend their Frank to a CMO.
  • A member may use official resources for communications related to the purpose of a CMO. Any such communications must comply with the Franking regulations.
  • Members may devote a section of their official website to CMO issues, but CMOs may not have independent web pages.
  • A member may use inside mail to communicate information related to a CMO.
  • Members may prepare material related to CMO issues for dissemination.
  • Official funds may not be used to print or pay for stationery for the CMO.
  • Members may refer to their membership in a CMO on their official stationery.


  1. ^ "Congressional Member Organizations: Their Purpose and Activities, History, and Formation" (pdf). Congressional Research Service. January 26, 2017. Retrieved April 11, 2018. 
  2. ^ "All-party Parliamentary Groups". BBC News. August 20, 2008. Retrieved April 11, 2018. 
  3. ^ "Members". Republican Main Street Partnership. Retrieved April 11, 2018. 
  4. ^ "Membership". Republican Study Committee. Retrieved April 11, 2018. 
  5. ^ David Hawkings (January 19, 2016). "The House's Ideology, in Seven Circles". Roll Call. Retrieved April 11, 2018. 
  6. ^ "Congressman Garamendi Selected as Co-Chair of Bipartisan American Sikh Congressional Caucus". garamendi.house.gov. May 22, 2014. Retrieved April 11, 2018. 

See also