Once the final ballots are counted tonight, we still might not know which party will control the U.S. Senate for the next two years. Susan Ferrechio of the Washington Examiner explains why.

The balance of the Senate could remain a mystery for several weeks after Nov. 8, thanks to an unusual election process in Louisiana that is likely to leave the political outcome of its Senate race unknown for another month.

With the Senate margin already expected to be razor-thin for either party, that could mean election night leaves the Senate hanging with 50 seats for one party and 49 for the other. Republicans today have 54 seats in the Senate, but are defending many more seats than Democrats, and are widely expected to lose a few and maybe even lose the majority.

“Suddenly, Louisiana could cause the Senate to break even or give 51 votes for either one of these political parties,” University of Louisiana political science professor Joshua Stockley told the Washington Examiner. “That could change the calculus for either party tremendously.”

It could also leave the Senate in disarray for weeks as the two parties wait for the Louisiana runoff in order to find out who will control the majority. November is a critical organizing period for lawmakers in Congress who elect leaders and establish committee ratios based on the outcome of the election.

Congress must also pass a fiscal 2017 spending bill to keep the government operating past a December deadline. An uncertain majority in the Senate will leave the parties without the much-desired leverage that would come if either Democrats or Republicans knew they would control the gavel in 2017.

Instead they might be left waiting for Louisiana.

Louisianans call their November contest the “jungle primary” and it lives up to the name by allowing every candidate from any party onto the November ballot without culling the list.

This election, the ballot includes 24 Senate candidates, including eight Republicans, eight Democrats and a bevy of Libertarians and Independents. The seat was left open after Sen. David Vitter, a Republican, decided not to run for re-election.