US President Joe Biden speaks during an American Rescue Plan event in the Eisenhower Executive Office Building in Washington, D.C., on Friday, Sept. 2, 2022.

President Joe Biden excoriated "MAGA Republicans, the extreme right and Trumpies" on Monday, pitching his Labor Day appeals to union members he hopes will turn out in force for his party in November.

"The middle class built America," Biden told a workers' gathering at park grounds in Milwaukee. "Everybody knows that. But unions built the middle class."