For four years, local business interests have enjoyed majority representation on the Jefferson Parish School Board, watching in satisfaction as the five board members they backed successfully in 2010 elections enacted key elements of the business groups’ plan to improve the parish’s school system.

But after voters sent two teachers union-backed candidates into office in Saturday’s runoff election, the board’s three remaining business-backed members will soon have to adjust to a much different political environment: life in the minority.

The board’s balance of power could have swung either way Saturday, giving either side a 5-3 advantage or, if the two races split, a 4-4 breakdown with unallied member Mark Morgan becoming a critical swing vote.

But the victories of Melinda Doucet and Ricky Johnson over incumbent Mark Jacobs and Rickeem Jackson, respectively, represent a potential sea change from the policy agenda overseen by Superintendent James Meza, who has championed measures opposed by the Jefferson Federation of Teachers.

Doucet beat Jacobs 53 percent to 47 percent, while Johnson won with 54 percent to Jackson’s 46 percent.

During Meza’s tenure, the school district scrapped its contract with the union, a traditional agreement viewed very differently by each faction.

To the pro-business side, collective bargaining agreements prevent school systems from making sure teachers are held accountable for their students’ level of achievement. Unions counter that the agreements are the only way to provide teachers the job security necessary for them to focus on their mission to teach children and that “union busting” is less a means to a desired end than a goal in itself.

Not surprisingly, the two sides don’t see eye-to-eye on the results of four years of pro-business rule.

The business faction’s supporters tout improvements in the district’s ranking. The system jumped from 52nd in the state in 2010 to 36th last year, and its score from the state Department of Education rose from a D to a B.

It is often noted, however, that a new scale was implemented during the same period, and the district’s B actually would have been a C in an apples-to-apples comparison.

Union leaders also argue that the system was already making improvements before the 2010 board came to power and that much of the jump in scores touted by the business faction came from closing seven failing schools and dispersing their students throughout the system.

One of the first major decisions to be made by a board now dominated by educators or explicitly pro-union candidates is the selection of Meza’s successor.

Meza announced his intention to step down late last year, but he agreed to extend his stay to provide stability first for students coming into the current school year and then for the system during a contentious election cycle.

The business groups, which include members of the Jefferson Business Council and the Louisiana Association of Business and Industry, had high hopes that voters would validate the changes the board had enacted over the past four years. At a recent Jefferson Chamber of Commerce luncheon, speakers urged attendees to help keep up the momentum and warned that losses at the polls could halt efforts to overhaul the system.

Not all business-backed candidates lost in this round of elections. In the Nov. 4 primary, incumbent Larry Dale defeated Jefferson Federation of Teachers President Meladie Munch, incumbent Sandy Denapolis-Bosarge defeated former School Board member Gene Katsanis and Melinda Bourgeois beat union-backed Glenn Mayeaux in the race for the open seat in District 4.

However, the American Federation of Teachers, the national organization overseeing the Jefferson teachers union, put $446,000 into the race, $200,000 more than the total raised this year by all 19 candidates running for seats on the board.

On top of Saturday’s victories by Doucet and Johnson, business-backed incumbent Michael Delesdernier fell to Marion “Coach” Bonura, a former educator and coach, and union-backed incumbent Ray St. Pierre defeated business-backed candidate Ray Griffin in the Nov. 4 primary. In addition, union supporter Cedric Floyd, with whom Delesdernier frequently butted heads, easily won re-election in a three-way race in the primary.

Time will tell whether the next four years will meet the expectations of many teachers and the union, who warned that a repeat of the past term would further divide the board from its educators and make many experienced teachers decide to leave the system.

Follow Chad Calder on Twitter, @Chad_Calder.