Well, we have the party primaries to determine the final choice of candidates for the November ballot. Parties actually on that ballot get there from "weight of numbers" of registrants, etc. In recent times, then, we have the Dumbs, the Pubes, the Reformers and a write-in blank.
To recap the Electoral College system, each state, based on its population, has a certain number of votes in the EC. It's a "Winner take all" system, so whoever gets a majority in a state gets all the state's votes.
The Electors in the EC are not legally bound to cast their votes for a given candidate, but in general it's a pro forma affair. The Electors pay no attention to any specific issues of the campaigns. They do their expense-paid trip, show up and do their thing, and go home. It's reported on Page B 9 in the average paper, since the "Official"
results were known on election night.
Hope this helps, FWIW, Art