Twenty-one Iowa public employees unions representing state workers for collective bargaining of contracts have all won re-certification elections, according to unofficial results from the Iowa Public Employment Relations Board.

Unofficial results for than 400 additional local bargaining units showed the vast majority were also winning re-certification. That includes bargaining units for cities, counties, school districts, community colleges and area education agencies.

The preliminary counts, which are subject to challenges for 10 days, show that state workers overwhelmingly decided they wanted to continue being represented by public employees' unions. The votes were required by a 2017 law.

The state workers' elections involved public employees' unions for the state's executive branch, judicial branch and the state universities.

At least 22 small local bargaining units failed to obtain re-certification because of a lack of yes votes from a majority of eligible public employees. If an eligible voter does not vote in a union election, it is essentially the same as a no vote.

Voting closed at 9 a.m. Monday for the union elections and the board began tallying ballots around mid-morning after obtaining them from an election service vendor, said Mary Gannon, a Public Employment Relations Board member. The board finished counting ballots Monday night.

Under legislation approved by the Republican-controlled Iowa Legislature last year and signed by former Gov. Terry Branstad, Chapter 20 of Iowa law was dramatically scaled back to reduce the rights of public employees. One of the new requirements is that all public employees' unions must be re-certified 10 months prior to the expiration of a contract with a government employer.

The largest state workers union involved is Council 61 of the American Federation of State, County and Municipal Employees. The AFSCME technical bargaining unit — the largest up for re-certification — had 4,762 workers eligible to vote. A total of 3,619 voted yes and just 15 voted no. The AFSCME fiscal and staff unit — the second largest — had 4,389 eligible to vote. A total of 3,295 voted yes and just 20 voted no.

In the Des Moines Independent Community School District, the Des Moines Education Association was approved with 2,769 yes votes and 33 no votes.

All state contracts are two-year contracts under Iowa law, and all expire in 2019. For local governments and school unions, the maximum length of a contract is five years.