With experts constantly looking for the fatal flaws hackers may try to leverage, he says physical security of the machines themselves also remains a concern.
Questions like where are the machines stored during the year and who has access to them.
"So that no one can come in and put a thumb drive into the machine and actually try to change the voting as the voting is occurring," said Dr. Mattox.
And with the eyes of the nation fixated on those results...it'll be a test of capability that keep democracy a level playing field.
On a national level, multiple federal agencies including the FBI, Department of Justice, Department of Homeland Security, and the Office of the Director of National Intelligence said the government has been working "in unprecedented ways to combat influence efforts and to support state and local officials in securing our elections, including efforts to harden election infrastructure against interference. Our goal is clear: ensure every vote is counted and counted correctly. At this time we have no indication of compromise of our nation's election infrastructure that would prevent voting, change vote counts, or disrupt the ability to tally votes."