Editor's Note: (Critical Counties is a CNN series exploring 11 counties around the country that chief national correspondent John King has identified as key in the 2016 election. These counties could play an outsize role in the election and offer an instructive example of what the political parties have accomplished. El Paso County is the ninth county in the series, which runs through Election Day. Explore the other critical counties.)
For months now, polls have indicated the swing state of Colorado will remain blue. Hillary Clinton's ground game there has been said to outperform Donald Trump's by several measures. As votes come in, the Democrats appear to have gotten the edge.
But there's one patch of ground the Trump campaign has not conceded: El Paso County, Colorado. This reliably Republican territory has seen a fair bit of attention, and it is clearly where the Trump campaign has tried to take a stand.
This county's population is white relative to the rest of the state, and it pulled strongly in favor of Republican nominee Mitt Romney over President Barack Obama in 2012. In a state whose politics have been overshadowed somewhat by legal pot, the people of El Paso County have so far elected not to join in.
But Trump's controversial candidacy could make room for third-party insurgency dragging down his numbers, move some would-be Republican voters toward Clinton and drive others not to mail in their ballots.
El Paso County could prove to be a strong indicator of whether Trump can overcome his many obstacles to deliver on a cut-and-dry Republican opportunity in a swing state.
Of course, there is one more thing to keep in mind. This election has seen far more talk than usual about nuclear weapons, and El Paso, home to NORAD, has nukes on the brain. Search data from Google shows El Paso is 80% more interested in the Iran deal than the US on average.
Trump criticizes the Iran deal almost every day, while Clinton has made a point of saying she is afraid of Trump's finger on the nuclear button.