The U.F.T. has greater influence in city politics than District Council 37, a larger union that represents many child care workers, after-school employees and other essential workers, along with many white-collar employees who have worked remotely during the pandemic.

Many other child care workers around the country — the majority of whom are nonwhite — are in unions that do not have the same political clout as teachers’ unions, and many are not unionized at all. That dynamic, along with differences in teaching credentials, helps explain why child care workers tend to make significantly less money than public schoolteachers.

Randi Weingarten, president of the American Federation of Teachers, a national teachers’ union that represents about 100,000 child care workers along with teachers, said that the last year is a clear argument for a more robust unionization effort in the child care industry.