Iow, while it’s possible, of course, and we should always have impenetrable vote tallying technology in place in all States (and we do not), focusing on that as the smoking gun is a red herring. The real trove of information the Russians were after was in fact the voter registration information, because through that information they could effect their social media propaganda war and target the people they know are actually going to vote before they get anywhere near the voting booth.
Why is that any different than the same things the GOP/Trump camp (or the DNC/Hillary camp) were doing? Simple. As a third party intent on destroying one side while boosting another, Putin had a distinct advantage in that he could play both sides against each other from the outside looking in, but more importantly, he could divide the Dems while unifying the Repugs because he didn’t have to bother with the “one side vs. another” traditional approach. Social media is unique (and he knew it) in that it is only effective when pitting like-minded people against each other. It does not good at all when pitting diametrically opposed people against each other. They just butt heads and nothing is ever resolved.
And, yes, thanks to Sanders not leaving the primaries when he should have (in May, if not March), Putin had an additional six months or so of prime division to further push the wedges that in turn Sanders’ camp would provide and/or react to and promote while at the same time Trump campaigned unopposed, allowing Putin to do nothing but strengthen and unify the right (or, at least Trump’s “base”

Which makes one wonder whether or not Putin was behind the onslaught to keep Sanders in the race in some fashion. It certainly would have been to his advantage to do so and there were many ways he could attempt such influence, but the real point is that his own experiences with weaponizing social media in Russia (and the many studies that have been done in this country proving how Facebook alone can push a significant needle—along the lines of twenty to thirty percent), there was no need to physically alter the vote tallies when a country has such an assinine, castrated and outdated system as the Electoral College. As we saw, all that was required to change the outcome was a minuscule change in percentages and that only in certain counties within just three states.
Again, the effect of Facebook being able to move a 20% needle was way beyond what was required. Just moving it 2% (or much less in most areas) did the trick.
The first step in trying to secure our voting is to either eliminate the EC altogether, or to reinstate its original mandate. That’s the horrible irony of all of this; the popular vote is the only vote there is. Since Congress did not just remove the EC, 48 of the States instead castrated it by establishing their own internal rules for their electors, such that they are not allowed to go faithless as was the original mandate. Every State but two affirms the notion of the popular vote determining the winner, the only problem being that due to the EC rules, certain State electors count more than others.
So while the popular vote is actually the only vote, the Country is effectively gerrymandered too and that’s the real problem. Take that away and a foreign country would need to eliminate millions of votes to even come close to changing the outcome, instead of just 55,000.