DENVER (AP) — Colorado voters are picking between ex-Gov. John Hickenlooper and former state House Speaker Andrew Romanoff as the Democratic nominee to take on Republican Sen. Cory Gardner.

The Democratic primary for Senate tops Colorado’s primary election slate on Tuesday. Colorado’s congressional party primaries are mostly a formality, with six of the state’s seven incumbents going unchallenged. Their would-be opponents in November are going unchallenged as well. Only Republican Rep. Scott Tipton faces a party opponent. Two Democrats are vying to run against him in November. Unaffiliated voters now make up 1.4 million of registered voters, along with 1.1 million Democrats and 969,000 Republicans. 

Stay tuned Tuesday night on KREX 5 and Fox 4 for voter turnout and poll updates on the Western Slope for Colorado’s Primary.