Two Democrats are running against each other in Colorado’s Democratic primary for U.S. Senate on June 30: incumbent U.S. Sen. John Hickenlooperand state Sen. Julie Gonzales. Sen. John Hickenlooper, 74, served as Denver’s mayor from 2003 to 2011 and as governor of Colorado from 2011 to 2019. He ran for president in 2020 before switching to the U.S. Senate race, where he unseated Republican U.S. Sen. Cory Gardner. Before entering politics, Hickenl…