Louisiana's New Primary System Just Passed Its First Real Test

For nearly fifty years, Louisiana let every voter, regardless of party, pick the nominee for every office on the ballot. This year, for the first time since Edwin Edwards signed the jungle primary into law in 1975, that changed for some of the state's most important elections, and the results validated exactly what Governor Jeff Landry said they would.

Louisiana's shift to a closed party primary for U.S. Senate, U.S. House, the Louisiana Supreme Court, the Public Service Commission, and the Board of Elementary and Secondary Education traces back to legislation Landry pushed through in a January 2024 special session, carried by Rep. Julie Emerson, R-Carencro. Under the new system, Republicans choose the Republican nominee and Democrats choose the Democratic nominee, full stop, with no-party voters allowed to pick a side for the primary but required to stick with it through any runoff. It was a deliberate break from the old jungle primary, where Democrats and independents could cross over and shape a Republican race, and where a well-funded moderate could sometimes survive a divided conservative field simply by consolidating everyone who wasn't a true conservative.

The U.S. Senate race gave the new system its first real workout, and the outcome speaks for itself. Sen. Bill Cassidy, who angered the conservative base with his 2021 vote to convict President Trump, finished third in the May 16 first-round primary with roughly a quarter of the vote, failing to make the runoff at all. Under the old jungle primary, it's entirely plausible Cassidy survives that first round by picking up crossover support from Democrats and independents eager to keep a more moderate Republican in office, the same dynamic that has protected establishment-friendly candidates in Louisiana for decades. Under the closed primary, that safety net didn't exist. Only Republican voters decided the Republican nominee, and they decided decisively for Julia Letlow over John Fleming in the June 27 runoff, 57 percent to 43 percent.

That is precisely the outcome supporters of the closed primary promised: a system where the party's own voters, not a broader and more ideologically mixed electorate, choose who represents them. Lt. Gov. Billy Nungesser has openly said he believes the closed primary was adopted in large part to make it possible to defeat Cassidy, and whatever one thinks of that motive, the mechanism worked as designed.

The reform hasn't been without friction, even within Republican ranks. Senate President Cameron Henry has said he expects lawmakers to file bills unwinding the system after this election cycle, citing voter confusion and the added cost of running closed primaries alongside the state's traditional jungle primary for other offices. Secretary of State Nancy Landry's office has acknowledged the logistics are real, sending mailers to educate voters on a process many hadn't encountered before, and no-party voters, who make up roughly a fifth of the electorate, had to adjust to being asked to choose a ballot for the first time. Those are legitimate administrative concerns worth debating as the legislature considers whether to keep, expand, or scale back the system in future sessions.

But administrative friction is a different question from whether the reform accomplished its core purpose, and on that score the 2026 cycle delivered a clean answer. Louisiana Republicans got to pick their own nominee for one of the state's most consequential offices without outside interference diluting the result, and they picked the candidate carrying President Trump's endorsement and the backing of the state's Republican leadership. Whatever changes lawmakers make to the mechanics going forward, the first real test of closed primaries in Louisiana showed the concept works exactly as its architects intended.