Here in Long Island, NY, you vote via a huge sheet with several rows -— Democrat, Republican, Conservative, Green, Workers Party
Each row has its own candidate and all you do is BLACKEN the oval of the person you want to vote for.
The paper is then read via an electronic reader, and automatically tallied.
They should be able to know how many votes Trump/Pence had vs. Biden/Harris immediately.
The computer holds those numbers, but they actual process of counting does not begin until 3 Nov. Theoretically, nobody knows what those early votes look like until Election Day. That was how it was explained to me anyway.