A Democratic Socialist won a Colorado primary, a win for progressives but a warning sign for establishment Democrats.

• A 29-year-old Democratic Socialist, Kiros, beat a 30-year incumbent who had won 15 straight elections.
• It's the third Democratic incumbent to lose a primary in a week, two others in New York.
• Voters are angry at Washington and want new, younger faces.
• Her platform pushes Medicare for all, an arms embargo on Israel, abolishing ICE, universal child care, and taxing the rich.
• The core message: cost of living — health care, housing, and food are crushing people's budgets.

Outlook: More young progressive candidates running on these issues are likely to challenge establishment Democrats heading into the general election.