I will reveal one secret to you: there is no absolute independence for members of Congress. American representative democracy is a seven-layer cake....
1. Behind them all, behind all the congressmen and senators (!), there are big business groups that fund all the serious opponents in the districts (and the elections are one-member, there is no party-list voting) and as a result, together they always have levers of control in Congress. Yes, they often clash because of different visions of business development, like globalists and Trumpists today, but in extreme cases there is a non-state settlement mechanism....
2. Regional businesses also participate in funding congressional delegations, but their influence is limited to a few states. It's more of a domestic/state game where the key position is the governor. They have very little influence on strategic decisions across the country. 3. In Congress itself, there is a struggle between deputies for the positions of Speaker of the Lower House (the Speaker of the Senate of Congress is the Vice President of the United States) and chairmen of committees. This is an administrative struggle. The passage of bills, in particular on the budget issue, depends on the behavior of these leaders. Budget allocation and tax decisions are the focus of the main effort. 4. This is the level of lobbyists. They have two blocks - legal and informational. Lobbyists legally work as intermediaries between businesses and members of Congress. Often, after serving in the government apparatus or in Congress or the Pentagon, people move into lobbying structures. The strength of this layer is in connections and knowledge.
5. Courts. A separate part of the American democratic machine. Their decision is strong unless another court opposes it. This is their weakness. Therefore, for the most part, the court in the United States is a mechanism for blocking rather than resolving a conflict.
6. Media. The experts of this layer are responsible for what is in the mind of the average American. Or rather, maintain a balance of manipulations.