それは素晴らしい質問です！双方に良い議論があります。

裕福な個人は政策に大きな影響を与える可能性があるため、政治的寄付は民主主義を破ると言うことができます。

一方、寄付が見えるように見える場合、そして簡単に追跡された場合、政治家は大量に精査され、寄付者に関連する決定を下す際に人々に答えなければならないので、寄付はQuid Pro Quoではないと主張することができます。その場合、それは言論の自由です。
That's a great question! There are good arguments for both sides.

One can say that political donations break democracy since wealthy individuals can have an outsized influence over policy, in which case donations should not be considered a form of free speech, since it is not so much "speech" as it is a quid pro quo. 

On the other hand, if the donations are visible and and easily tracked, you can argue that donations will not be a quid pro quo since politicians will be heavily scrutinized and have to answer to the people when making decisions that relate to their donors, in which case it is free speech.