Why did the McCutcheon majority view political contributions as connected to freedom of speech and association?

In McCutcheon v. Federal Election Commission (2014), the Supreme Court majority concluded that aggregate contribution limits violated the First Amendment because they infringed upon the rights of freedom of speech and freedom of association.1

The Court viewed financial contributions as a protected form of political expression, reasoning that individuals have a right to support multiple candidates and political parties that share their views. By capping the total amount an individual could contribute across various committees, the government was seen as restricting a citizen's ability to participate in the political process and associate with the groups of their choice.12

The majority held that these aggregate limits were not sufficiently justified by the government’s interest in preventing the reality or appearance of quid pro quo corruption. While the Court maintained that "base limits" on contributions to individual candidates remained constitutional to prevent bribery, it determined that aggregate limits did not serve that same purpose and instead unnecessarily burdened the ability of citizens to engage in political advocacy.312