Individual donors are the primary source of funding for political parties in the United States. In the 2020 election cycle, individuals contributed over $3 billion to political parties.

The Supreme Court's decision in Citizens United v. Federal Election Commission (2010) overturned restrictions on corporate and union spending in elections. This has led to a significant increase in corporate donations to political parties.

Increased party funding can lead to increased polarization, increased corruption, and decreased voter turnout. When parties have more money, they can spend more on advertising and other campaign activities, which can make it more difficult for challengers to compete. This can lead to a more polarized political landscape, in which the two major parties become more entrenched in their positions and less willing to compromise. Additionally, increased party funding can lead to increased corruption, as parties may be more likely to engage in unethical or illegal activities in order to raise money. Finally, increased party funding can lead to decreased voter turnout, as voters may become disillusioned with the political process when they see that the parties are more interested in raising money than in addressing the needs of the people.

There are a number of potential reforms that could be implemented to address the impact of party funding on elections. These include public financing of elections, campaign finance reform, and term limits for elected officials. Public financing of elections would provide candidates with a set amount of money to run their campaigns, which would reduce the need for private donations. Campaign finance reform could limit the amount of money that individuals and organizations can donate to political parties and candidates. Term limits for elected officials would prevent politicians from serving in office for an extended period of time, which could reduce the influence of money in politics.

Political parties play a vital role in a democracy. They represent the interests of their constituents, develop and implement public policy, and provide a forum for debate and discussion. By doing so, political parties help to ensure that the government is responsive to the needs of the people.