It was a rare triumph for the democratic socialist candidate seeking to unseat the mayor of Minneapolis. After a chaotic party convention held last month, State Sen. Omar Fateh clinched the endorsement of the local Democratic Party, becoming the first mayoral candidate in the city to get that support since 2009.

But the edge was short-lived. On Thursday, Democratic Party officials in Minnesota took the rare step of withdrawing the Minneapolis chapter’s endorsement, citing “substantial failures” during the convention, which was marred by technological and procedural irregularities. It’s a blow for progressives in the city who championed Fateh’s victory and characterized it as a win for the Democratic Party’s left flank nationwide.

A draft report released by the committee notes the challengers to Fateh’s endorsement did not have to prove alleged violations, or system breakdowns, would have led to a different outcome for the challenges to be examined by the state party.