McALLEN, Texas (Border Report) — A special election to fill the remaining term for a South Texas congressional border seat is being held Tuesday.

Two Republicans and two Democrats are all vying to fill Texas’ District 34 seat for the remainder of the year. It is a seat that former U.S. Rep. Filemon Vela Jr., a Democrat from Brownsville, held since 2013 but stepped down on March 31 to pursue other interests, and that has been affected by redistricting.

GOP candidate Mayra Flores has spent almost $1 million on TV ads that promote border security.

She was born in Tamaulipas, Mexico, and tweeted last month about how her family migrated “legally” to the United States. She is the wife of a U.S. Border Patrol agent.

A win could set up Flores ss the incumbent candidate for the general election in November.

Former Cameron County Commissioner and Judge Dan Sanchez, of Harlingen, Texas, is running as a Democrat. Republican Juana “Janie” Cantu-Cabrera, and Democrat Rene Coronado are also in the running.

The race will go to a runoff later this summer if no candidate receives a majority vote on Tuesday. Polls close at 7 p.m. CT.

The winner of Tuesday’s special election will hold the Gulf Coast seat only until January when the winner of the November election takes office.

In November, Flores will face U.S. Rep. Vicente Gonzalez, who lives in McAllen and currently represents District 15. He is running as the Democratic candidate for District 34 in November after the Texas Legislature changed voting boundaries and relocated his home from District 15 to District 34.