Republicans or Democrats; it doesn't matter. It shows voter fraud with absentee ballots has occurred despite widely publicized statements saying voter fraud is a myth. It isn't.
The fact is there are literally hundreds of voter fraud cases with convictions. https://www.heritage.org/voterfraud
It is also foolish to look at the percentage of votes determined to have been fraudulent as in indicator of the importance of the problem. First the number of those caught is likely a fraction of the total number of fraudulent votes incorrectly counted. Second, the margin of victory in a close race, say Florida in 2000, may be smaller that the number of fraudulent votes cast.
Mail-ins with legal harvesting makes voter fraud way too easy. I forecast both sides will cheat like crazy. They'd be foolish not to. It's so simple to do and so hard to get caught.
Hackers may send in a few thousand for cartoon characters just to show they can mess with the system. Meanwhile foreign countries will send in their own phony ballots. It will be a free-for-all. You could easily end up with twice as many ballots cast as there are registered voters. The Supreme Court may have to throw out all votes not cast in a voting booth. In another scenario, the overwhelmed vote counters are unable to count half the votes by the time the election needs to be certified. Why do some people want to court such a disaster? If Democrats had confidence they truly had an electoral majority, they would opt for limited mail-in voting. It would only be done in states that have done it before and there would be no harvesting anywhere. They would also want to tighten up on security for absentee ballots. They would want to make their victory iron-clad, not subject to endless challenge and unresolvable doubt.