“We know that many Americans are struggling,” the group said in a release. “Too often hard work is not rewarded, and not enough is being done for workers to adjust to the rapid pace of change in the economy.”

Such pronouncements have yet to produce a tangible change in many Americans’ daily lives.

One in four workers say they have unpredictable work schedules, which can have insidious effects on family life. One in five adults who are employed say they want to work more hours. Annual wage growth has struggled to reach 3 percent. And nearly 40 percent of Americans, a Federal Reserve report found, are in such a financially precarious state that they say they would have trouble finding $400 for an unexpected expense like a car repair or a medical bill.

Keenan Harton, 45, juggles two jobs, one at a Biscuitville fast-food restaurant that pays $8 an hour, and another at a hospital laundry in Durham, N.C., that pays $10.50 an hour. Often he shows up for work at the fast-food job for an eight-hour shift, only to be sent home after a couple of hours if business is slow.

“It’s real hard to find a full-time job that’s actually going to pay over $10 an hour,” said Mr. Harton, who has a high school diploma.

Four hundred fifty miles north, in New Jersey, Sonia Johnson’s last job was in August, a four-week assignment. “But my last full-time direct hire was back in 2009,” said Ms. Johnson, who worked in the human resources department of a pharmaceutical company until she was laid off. “For me, it’s been all through an agency, working as a contractor.”

Ms. Johnson, 55, who has a college degree, said she had kept her skills up to date by using grant money from the state’s labor department to take courses. “I have really good technical skills,” she said.

Asked how many jobs she had applied for, Ms. Johnson hesitated. “It’s almost embarrassing,” she said. “At least 500.”