[Cletus.D.Yokel]

My thoughts stemmed from the Constitutional aspect that States can format elections as they see fit.
States can just up and say, “mail-in elections”.
But, to do that, one would need to encumber the US Post office, a federal intermediary.
Once mail is in the mailbox, it becomes federally protected.

[Publius]

The Times, Places and Manner of holding Elections for Senators and Representatives, shall be prescribed in each State by the Legislature thereof; but the Congress may at any time by Law make or alter such Regulations, except as to the Place of Chusing Senators.

Congress not only sets the date for federal elections but can determine how they are conducted. For example, in 1826 Congress ended property qualifications for federal elections. Those qualifications still existed for the election of non-federal officeholders.

Congress can mandate voting in person rather than by mail. Congress can even mandate throwing out existing voter rolls for federal elections due to corruption and mandate that people re-register with the requirement that voters provide proof of citizenship and proof of residency. Congress can even mandate Voter ID.

[little jeremiah]

My thoughts stemmed from the Constitutional aspect that States can format elections as they see fit.
States can just up and say, “mail-in elections”.
But, to do that, one would need to encumber the US Post office, a federal intermediary.
Once mail is in the mailbox, it becomes federally protected.

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

And now a Trump supporter is head of the USPS.

[Cboldt]

-- Once mail is in the mailbox, it becomes federally protected. --

That's not a comfort.