Late returns and recounts were occasional exceptions. And of course there was always some corruption.
The big procedural changes that reversed the trend were vote by mail and early voting.
Who asked for those?
Lazy-assed Americans, that’s who.
Answer to your question re mail-in ballots - don’t know about early..That has to be very recent! This is interesting:
“”Mail-in voting, which is also known as absentee voting, has essentially been around for as long as the U.S. has been an independent country. According to The U.S. Constitution, the earliest examples of mail-in voting date all the way back to 1775 during the American Revolution, when a team of soldiers from the Continental Army sent a letter to their hometown, requesting to have their votes counted in a local town election.
There were also examples of soldiers using absentee voting during the War of 1812, and in the Civil War, when it was officially turned into a normal option for all citizens serving in the military. Mail-in voting, however, didn’t become an option for non-military citizens until around 1911, when states began allowing citizens to do it as long as the voter had a written “excuse” for not being present. Now, it’s available in all 50 states, that is, unless Trump forbids it in the 2020 election””