BUCKLEY v. VALEO Per Curiam tempt to exclude minor parties and independents en masse from the Act's contribution limitations overlooks the fact that minor-party candidates may win elective office or have a substantial impact on the outcome of an election.41 In view of these considerations, we conclude that the impact of the Act's $1,000 contribution limitation on major-party challengers and on minor-party candidates does not render the provision unconstitutional on its face. 2. The $5,000 Limitation on Contributions by Political Committees Section 608 (b) (2) permits certain committees, designated as "political committees," to contribute up to $5,000 to any candidate with respect to any election for federal office. In order to qualify for the higher contribution ceiling, a group must have been registered with the Commission as a political committee under 2 U. S. C. § 433 (1970 ed., Supp. IV) for not less than six months, have received contributions from more than 50 persons, and, except for state political party organizations, have contributed to five or more candidates for federal office. Appellants argue that these qualifications unconstitutionally discriminate against ad hoc organizations in favor of established interest groups and impermissibly burden free association. The argument is without merit. Rather than undermining freedom of association, the basic provision enhances the opportunity of bona fide groups to participate in the election process, and the registration, contribution, and candidate conditions serve the permissible purpose of preventing indi41 Appellant Buckley was a minor-party candidate in 1970 when he was elected to the United States Senate from the State of New York.