Some of the nation’s largest labor unions representing nurses and public school teachers are spending heavily on leftist causes and candidates ahead of the 2026 elections.

While their ostensive purpose is to negotiate wages, employee benefits, and workplace conditions, these unions continue to pour resources into critical races that could change the political makeup of Congress, as Democrats seek to retake the majority in November and progressive challengers, leaning on anti-establishment messaging, look to edge out more centrist opponents in primary upsets across the country.