Analyzing Changes in Partisanship in Absentee Voting

I asked this same question a few months ago, but I'm reposting for clarity. I'll try and describe the thinking behind what the hypothesis I was trying to test was, and hopefully you can tell me how I'm misusing statistics. In 2020, everyone observed that absentee ballots were much more Democratic than usual, as Democrats maintained quarantine and mailed in their ballots. Conspiracy theorists on the Right attributed this to absentees being tampered with or fraudulent, those on the Left theorized precinct voting machines might be hacked while absentee ballots were counted correctly. I thought about what sort of pattern one would expect to find if the change in "bias" had simply been voters in one party choosing to switch voting methods. If the total number of Democrats voting absentee in, say, Virginia, had gone up drastically, then the expectation would be that the overall increase in the percentage cast as absentee ballots would vary within the state such that it increased MORE in counties that had more Democrats and LESS in counties that had more Republicans. So the fairly Black cities and Black majority counties would go up more than the mountain counties out west. So I tried to look at Virginia and analyze the election results to see if that's what happened. For every election year from 2005-2023, I calculated the degree to which in precinct and absentee ballots were more or less Republican or Democratic, and what percentage of votes were cast with each ballot type in eac…