County unions typically get involved in mayoral elections, offering hands-on-deck, organization and campaign contributions to their preferred candidate.

“I think there’s going to be backlash” against Gimenez, said Greg Blackman, president of the Government Supervisors Association of Florida OPEIU Local 100, which represents nearly 4,600 professional employees and supervisors. “The employees are upset.”

Blackman’s GSAF union rejected the 4-percent concession Thursday by a vote of 94 percent to 6 percent. Five more unions have votes pending. (Two unions, representing aviation workers and firefighters, avoided the 4-percent concession altogether by agreeing to other givebacks.)

The impasse with the unions arose when Gimenez’s administration proposed the 5-percent healthcare contribution. Commissioners rejected that plan and took up the issue again only after the mayor vetoed their original decision.

It is unclear if the police union, which sued the county over its handling of the anticipated layoffs, will put the 4-percent concession before its 5,400 police and corrections members. John Rivera, president of the PBA, said the union believes Gimenez did not have the authority to veto the commission’s initial vote.

Commissioner Barbara Jordan, who negotiated the 4-percent compromise with Gimenez and swung the 7-6 vote in the mayor’s favor, urged county workers from the dais to reject extending the concession beyond this year.

“I do not support, nor will I support in the future, any money coming from employees,” she said. Of the employees, she added: “I’m sure they’ll know how to vote.”

Commissioner Audrey Edmonson, who favored the compromise, said from the dais that she worried non-union county workers would still have to pay the 5-percent healthcare contribution Gimenez imposed in July.

Those employees indeed will pay the higher percentage through the end of this fiscal year, spokeswoman Suzy Trutie said , though for next year, the mayor told commissioners he may consider a lower contribution from employees who make lower salaries.

About 2,800 workers out of the county’s approximately 26,600 employees are not union members.

Knowing he will need commissioners to sign off on his future reorganization and union-contract plans to avoid a second, potentially costly political clash, Gimenez sent board members a memo the day after they approved the compromise striking a conciliatory tone.

The budget is complicated, he wrote, and this year, “our debates have been frank, emotions have run high at times and we have not always agreed on the best course of action.“Ultimately, though, we have come together and fulfilled our obligation to balance the budget, and more importantly, we have joined together to do what I believe is in the best interest of that public that each of us has pledged to serve.”