Always remember that policy universally is promoted to further the agenda of a given party! Many republican politicians opt for the abolition of early/absentee voting, and democrats the opposite. Bear in mind that these policies are not just ideological rhetoric, but political play, intended to benefit the ruling party rather than the wider people.
How are states with mail in voting counted? We don’t vote at a polling station (and it’s glorious) on Election Day. We typically vote well before hand. They just get counted on Election Day.