What began as an ordinary Democratic gubernatorial primary in Wisconsin has quickly become one of the party’s biggest ideological battles, offering an early test of whether socialism can win statewide in one of the nation’s most important swing states.

Just nine days ago, Milwaukee County Executive David Crowley suspended his gubernatorial campaign and endorsed the then-Democratic front-runner, Lt. Gov. Sara Rodriguez (D-WI), appearing to clear the way for the establishment-backed candidate to consolidate support against state Rep. Francesca Hong, a socialist whose campaign had steadily gained momentum.