Many of their keynote proposals would create, or increase, minimum federal standards for compensation and benefits. Notably, nine of the 10 candidates who qualified for the next debate in September support a federal minimum wage of $15 an hour. The exception is the businessman Andrew Yang, who worries that a higher minimum wage would reduce employment. A potential variant, backed by Senator Michael Bennet of Colorado, one of the remaining candidates who did not qualify for the debate, would allow a lower minimum wage in less affluent areas. This could be sensible so long as exclusions are drawn narrowly.

There is also general support for a law guaranteeing paid family and medical leave.

Any such minimum standards are important, but insufficient. Most workers already earn more than the minimum and receive basic benefits. But in recent decades, workers have received a declining share of the nation’s economic output in the form of wages and benefits. The need is for changes in federal law to shift the balance of power toward workers.

One potential vehicle is a revival of the union movement. Only 10.5 percent of American workers were unionized in 2018; a new report from the Brookings Institution argues that the decline of private-sector unions is an important reason for the stagnation of wages and the rise of economic inequality. Some ideas for empowering unions have become table stakes in the Democratic race. Most of the candidates, for example, favor federal legislation to prohibit so-called “right to work” laws, on the books in 27 states, that allow workers in unionized workplaces to refrain from paying union dues . (Mr. Yang once again is an exception.)

Another necessary change is to reverse the racially motivated exclusion of agricultural and domestic workers from the full protection of federal labor laws. Senator Kamala Harris of California is leading the field on this issue. She has introduced a “Domestic Workers Bill of Rights” that would extend basic protections to the nation's caregivers and housekeepers — including a mandated minimum wage, eligibility for overtime and paid time off.

Other candidates, including Senators Bernie Sanders of Vermont and Elizabeth Warren of Massachusetts, and former Representative Beto O’Rourke, also have backed an end to that unjustified divide — as well as other measures to strengthen the hand of unions.