Gerrymandering, yo.
This is _such_ a US centric view. Guys, you have way a worst problem than elections. You have a party strongly pursuing getting rid of democratic results altogether.
Beyond the stated (That G word) the republican party is STRONGLY preparing the landscape to not recognize the results of the next election (Or the next one after that).
I actually have a bet with a friend about when the last democratic election is going to happen, and my money is on this last midterms being the ones (Gotta reckon, I wasn't expecting Gen-Z, and I'm gladly surprised I might be wrong).
Take for instance the last election in Brazil, where Lula beat Bolzonaro by the bare minimum: 51% to 49%. What would had been the results of such an election in the US? In 2016, Clinton won the popular vote by 2.1%, and _still_ Trump won the presidential race. In 2020, even thought Biden wan the popular vote by a large margin, the results were still down to a handful of votes [1]
The problem, as I see it, is that you have a democratic system that allows for suppressing democracy.
[1] https://www.npr.org/2020/12/02/940689086/narrow-wins-in-thes...