Prince George’s County Executive Rushern L. Baker III (D) received significantly more power over the county’s school system last year when the General Assembly passed legislation that allowed him to choose the school district’s school chief, appoint several board members and select the leaders of the board.

With primary elections for the county school board coming on Tuesday and four elected seats up for grabs, Baker is making a major push for an even greater say over how the school system functions, publicly backing four people who support his vision for the school system.

“It’s important to have more members of the school board who are open to working with the county and who understand that this is one government,” Baker said during a recent interview.

Baker sought complete control of the long-struggling school system last March after clashes with the school board about the selection of the new superintendent and concerns about the slow pace of improvement in student performance. Despite gains in recent years, the school system languishes near the bottom of Maryland’s statewide rankings.

Twelve candidates — including two people Baker appointed within his administration — are vying for four district seats on the 13-member board. The top two vote-getters in each nonpartisan race will face off in November’s general election.

Candidates are running to serve on the new hybrid board, created under the governance structure approved by the General Assembly last year.

Under the new law, Baker appointed three members to the board. After two elected board members resigned last year, Baker also selected their replacements. If Baker’s preferred candidates survive the primary and win the general election, the county executive will have had a hand in selecting or backing a majority of the board.

David Cahn, the co-chairman of Citizens for an Elected Board, which fought Baker’s takeover of the system, said he is concerned about the prospect of Baker essentially having control over all issues affecting the school district, including budget and personnel matters.

“Our children are too important to get caught up in partisan politics,” Cahn said, adding that board members should not have to worry about whether Baker would approve the decisions they make.

The county executive has endorsed Lupi Grady, a new appointee to his education commission, in her challenge against incumbent Peggy Higgins in District 2. Both candidates will move on to the general election.

In District 3, Amber Waller, who has served on the board since 2007, is fending off a challenge from Clarence Emmanuel of Hyattsville and Dinora A. Hernandez, who works for Baker as a liaison to the Latino community and is his choice for the seat.

Baker has endorsed Vice Chairman Carolyn M. Boston, who initially fought Baker’s takeover effort but quickly reversed her stance and was selected by Baker to serve as vice chairman.

Boston is facing a challenge from Pat Fletcher, a former board member, and Darin Kenley, an educational consultant and former teacher. Neither of Boston’s challengers are new to campaigning: Kenley unsuccessfully ran for the seat in 2010, and Boston ousted Fletcher from her seat on the board four years ago.

Four candidates are running to fill the District 9 seat held by Sonya Williams, a civil engineer and the president of a parents, teachers and students association. Williams was sworn in as a board member in January, after Donna Hathaway Beck abruptly resigned.

The newcomers challenging Williams are Domonique A. Flowers of Clinton, Johnnie R. Isaac of Brandywine and Denise M. Joseph of Upper Marlboro.

Baker said his team will distribute handouts for his preferred candidates on Election Day.

He recently recorded a robo-call for Boston, describing her as a “great vice chairman” who works well with his appointed chairman.