Congressional Caucuses, or Congressional Member Organizations (CMO’s), are registered on Capitol Hill through the House Administration Committee. They are Member and Senate groups organized for a common cause/legislative agenda. According to House Administration, they are required to have at least one Member of the House be an officer of the particular CMO. In order to form one, a Member of the House must submit a letter to House Administration stating; CMO name, Statement of Purpose, Officers of the CMO and contact information.

In the 110th Congress there were over 300 caucuses on Capitol Hill. Some have more influence and sway than others and range in importance as well. For example, some are organized just for the fun and enjoyment of Members such as the Congressional Soccer Caucus for fans of the sport and its promotion. Some are organized to promote and curtail types of legislation such as the Patriot Act Reform Caucus.

There are several caucuses that have significant legislative power. Among the most important are the Congressional Black Caucus, the Congressional Hispanic Caucus, the Blue Dog Coalition, and the Progressive Caucus. In addition, there are other caucuses which focus on specific areas of legislation, and often have influence on various issues, such as relations with Israel. Some of the caucuses contain influential Members or such a large group of Members, that their approval is necessary for one Party to get a particular piece of legislation through. Current and past CMO’s can be found at http://cha.house.gov/member_orgs.aspx.