The lazy and indolent who would allow someone else to mark their ballot are overwhelmingly D.
I live in Westmoreland County and none of my friends will vote via mail {unless they will be gone during the election day}.
As a poll watcher {not during the off year elections}, I know first hand that pubbies in general, do not trust the mail in vote process.
I don't even trust the in person process, but it's the best we have.
In my opinion, every voter must be a legal citizen, with photo ID, and proof must be provided to vote, regardless of method selected.
That is the standard in most countries, including Mexico, and almost all European Countries.