There is literally no way to reason these people out of the position they didn't reason themselves into.
Regarding this, I recently saw the counterpoint of Santa. Most people never reason themselves into believing in Santa, but they do reason themselves out of it. Obviously there’s cognitive development that happens in between in the Santa case, but a lot of people form their core political beliefs pretty young, so that may be true of politics as well.
I come from a deep blue state, but haven’t lived in the US in years and every time I get an absentee ballot, it’s too late to send it in. I still apply, but we’ll see if it comes in time