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President Trump lost Colorado by 5 percentage points in 2016, and he’s on pace to lose it by more this year. His most recent approval rating there was 39 percent, according to Morning Consult.

His unpopularity creates a problem for Cory Gardner, a first-term Republican senator from Colorado, who will be running for re-election this year — which makes Gardner’s behavior during the impeachment trial especially striking. Rather than act as the senator he is, with his own power to shape events, Gardner has served as a Trump loyalist.

Gardner has not expressed skepticism about the obvious lies Trump’s lawyers are telling. Gardner doesn’t seem concerned about Trump perverting foreign policy for his own personal interests. And Gardner has shown no interest in hearing all the relevant evidence by calling witnesses to testify.