But the real problem it modern politics is re-districting. That's the decisions that are made about the borders of districts in your state. You vote within your assigned district. In a very real sense, you are competing with all the other voters in your district to make YOUR vote count.
Let me give an example or two. If you are in a district that has an equal number of Republican and Democratic voters (and a smidgeon of 3rd party voters) your vote matters a LOT! It could be the ONE that decides a state or local election (rare, but it has happened). More possible, you and a few hundred voters make the difference in a state or local election. That really does happen more than you would think.
Statewide candidates come from local winners. National candidates come from Statewide winners. Presidential candidates are usually Governors or Senators and they almost all started in local elections. That local County Comissioner who won by 100 votes Tuesday may rise to the Senate or even President some day by that few 100 votes the first time.
Here is where the redistricting comes in. The winners want to get re-elected; they can't play in the game if they don't stay in the game. Did you know that district borders are NOT set in stone? They can be changed. And they GET changed. The winners get to redefine their voting districts almost at will (well, there are ballot questions, but they almost never lose). Their goal is to redefine their voting district to include as many of their own party/voters as possible. That insures that they will stay in office until they win a higher office or until their cold dead bodies are pried from their chairs.
In a general sense, I don't blame them. In the course of my office career, I had to defend "the existence of my job" through arguments and tactics I would not defend in my retired life. Every organism strives to live...
Originally in the US, voting districts were defined by close-knit communities, logical geographical boundaries, and county lines where possible. Then, some "genius" got the idea of arranging the voting districts to his benefit. His names was Gov Elbridge Gerry and he did this in 1812 in Massachusetts. To preserve his party control, he redrew the voting districts, one of which resembled a salamander.
It was dubbed a Gerrymander... The head, wings and feet were added for effect by a newspaper, but you can see where the image arose.
But the process has gotten out of hand. The original idea of local campaigns was that several qualified individuals, all well known to the communities, would be considered, and one chosen. Today, routinely gerrymandered voting districts are arranged by incumbents to assure that they will seldom, if ever, lose office. Incumbency reigns supreme!
Gerrymandered voting districts means that each one is more and more of one party. And when the district is more one-party controlled, it encourages the kind of extremism we see today (on both sides). The only vote that matters is the one-party primary, and that encourages the candidates to take position on the far edges.
I suggest a solution. A simple one, just for discussion. I want a great big inked grid stamp. Allow some one person to push it down on the state map blindly. Demand that the PRIME PURPOSE of district borders be "political competitiveness". Then demand a NON-partisan committee to arrange adjustments according to general population evenness for voting districts in best alignment with that grid.
Honestly politically competitive voting districts in every state would go VERY far in eliminating the extremism of candidates and winners in both parties and promote political competition. I can't think of anything else that would improve US politics so immediately and positively.