Campaign finance, also known as election finance or political donations, refers to the funds raised to promote candidates, political parties, or policy initiatives and referendums. Political parties, charitable organizations, and political action committees (in the United States) are vehicles used for fundraising for political purposes. "Political finance" is also popular terminology, and is used internationally for its comprehensiveness. Political donations to funds received by political parties from private sources for general administrative purposes.

Political campaigns involve considerable expenditures, including travel costs of candidates and staff, political consulting, and advertising. Campaign spending depends on the region. For instance, in the United States, television advertising time must be purchased by campaigns, whereas in other countries, it is provided for free. The need to raise money to maintain expensive political campaigns diminishes ties to a representative democracy because of the influence large contributors have over politicians.

Although the political science literature indicates that most contributors give to support parties or candidates with whom they are already in agreement, there is wide public perception that donors expect government favors in return (such as specific legislation being enacted or defeated), so some have come to equate campaign finance with political corruption and bribery. These views have led governments to reform campaign financing in the hope of eliminating big money influence.

The causes and effects of campaign finance rules are studied in political science, economics, and public policy, among other disciplines.