Swing states, and even individual precincts within those states, present a significant point of vulnerability when it comes to the threat of election interference because of their potential to impact the result in a presidential race, the current secretary of the Department of Homeland Security and one of her key predecessors both told senators Wednesday.
…
[L]ocal jurisdictions in places that can have an outsized effect on the outcome of national races — like Wisconsin, Pennsylvania and Michigan — will be forced to defend against cyber-threats posed by entire nation-state adversaries like Russia.
“The reality is: Given our Electoral College and our current politics, national elections are decided in this country in a few precincts, in a few key swing states," former DHS Secretary Jeh Johnson, who served under President Obama during the 2016 presidential election cycle, told members of the Senate intelligence committee. "The outcome, therefore, may dance on the head of a pin.”