Those verbal promises were first tested on March 9, less than a week after Mr. Bloomberg exited the race, when many field organizers were laid off and told they would be paid through the end of the month. Employees were encouraged to reapply to work for Mr. Bloomberg’s organization in six battleground states: Arizona, Florida, Michigan, North Carolina, Pennsylvania and Wisconsin.

But on Friday, campaign employees in those states learned that they would not be working through the general election either. The Bloomberg campaign circulated a new survey to employees, inviting them to add their names to a list that would be forwarded to the D.N.C. for potential hiring. The deadline to fill it out was March 25.

There was no promise of a job. Applicants would “be fed into the competitive hiring process,” the message said.

“I spent all that time talking to people in my district, telling them we were going to be there through November — that was hammered into us over and over again,” said Dallas Johnson, who began working as an organizer in Minnesota for Mr. Bloomberg in January. “For the people who got let go today, there are other things they could have been doing,” he said, adding they had “pretty much zero job prospects of getting hired right now.”

Ms. Conrad, who took a leave of absence to join the campaign last month, said Friday that she would be unable to reclaim her job as a labor union representative before the end of the year.

She expressed particular concern about losing health care at the end of the month in the face of the coronavirus outbreak.

“I was looking to get ahead and pay off medical bills,” said Ms. Conrad, whose son has Crohn’s disease and takes immunosuppressant drugs. “Now I’m looking at falling further behind on them.”