BATON ROUGE, La. (AP) — The voter registration deadline is nearing for Louisiana’s presidential primary, and officials are reminding the state’s voters that the election is a rare closed primary that allows only registered Democrats and Republicans to cast ballots.

Nearly all of Louisiana’s elections are open primaries, where all candidates regardless of party run against each other on the ballot — and all voters can choose among all the candidates.

But the April 4 presidential primary is a closed primary. Only Republicans can vote in the GOP primary to select the Republican nominee for president, and only Democrats can choose among the Democratic candidates for president. Those who aren’t registered with either political party cannot vote in the presidential primary.

Secretary of State Kyle Ardoin’s office said the deadline to register in person or by mail to vote in the election is Wednesday. The deadline for online registration is March 14.

Beyond the presidential primary, 24 parishes will have local races on the April 4 ballot. Those local elections are open primary competitions, where every voter can cast a ballot regardless of party.

Voters can check their registration, change their registration or register to vote online at www.GeauxVote.com, the parish registrar of voters office, public assistance agencies, libraries, and public schools.