Most of the people I know who plan to vote for him think of that as a good thing. It’s the whole “drain the swamp” thing that he’s been rallying people behind for years; they think bad actors in the government are trying to hold Trump down, and him being in jail is just another attempt to do that - from their perspective, electing him even while he’s imprisoned would be a big “fuck you” to those bad actors.
It’s sad that they can’t see that Trump himself is the bad actor, but to most of them, Trump is their last hope to hold on to their beloved world of racism and misogyny, free of any “woke bullshit.” They’ll overlook anything he says or does at this point, since they don’t see any other way forward than through Trump.