[shhrubbery!]

Agree, but provisional voters show up only on election day itself. So even though a well-organized election board might be prepared to do a good job authenticating them --in ordinary times-- these are no ordinary times.

I think many places are experiencing a large increase in provisional voters, and in urban areas this overwhelms the system. (Standard Alinskyite tactic.)

To some degree the increase in provisional voters might have backfired in this election, i.e. in so-called rural areas of so-called rust-belt states. I know in my small town, we had a higher-than-usual number of provisional ballots; I'm in a Republican area so they were probably mostly were for Trump.

[Alberta's Child]

Agree, but provisional voters show up only on election day itself.

Right. So do millions of other voters. The problems with fraudulent voting that you described are not limited to provisional voters.