Republican supporter Shaun Dashjian celebrates the moment when Donald Trump won the 2016 presidency at the Colorado Republican election night party Tuesday, Nov. 8, 2016, in Greenwood Village, Colo.

Jack Dempsey/AP Photo

Election night is a month away, and evening news outlets will be racing to call the winner. That doesn't always go well, of course. (2000, anybody?) But with new advents in technology, the accuracy for most race calls these days hovers at 99.8 percent.

Jim Clarke, a central regional director with the Associated Press, has been calling Colorado's elections for more than a decade. Clarke talked to Colorado Matters to help lift the veil on calling races.

There's a lot of math and percentages, for sure, but equally important is understanding the politics of the state. In Colorado, that means keeping an eye on Denver and El Paso counties, as well as Jefferson. Clarke doesn't call a statewide race until he sees numbers from the liberal, conservative and "bellwether-ish" counties, respectively.