U.S. Reps. Al Green and Christian Menefee appear headed for a Democratic primary runoff in May, which would set up a fourth election in about seven months for voters in Houston’s 18th Congressional District.

Both men were in a tightly locked race early Wednesday as votes were still being reported, according to the Associated Press.

The primary is a rare incumbent-on-incumbent clash forced by legislative Republicans who redrew the Texas congressional map last summer to create five new seats that are more favorable to Republicans. Green was drawn out of his district, the 9th Congressional District, and into the new 18th District.

While both men are incumbents for the district, Green has represented the area for more than two decades. Menefee, who was elected to fill out the late Rep. Sylvester Turner’s term in a January special runoff, has only been in Congress for a month.

The new district also contains far more voters from Green’s old district than Menefee’s. But Menefee has been running for office for nearly a year and had a robust campaign operation that pivoted quickly to the primary in the new district after the November special election and January runoff in his current district. 

Green defeated an incumbent Democrat in 2004 after a different episode of mid-decade redistricting transformed a majority-white Houston Democratic seat into a district with a Black and Latino majority. He has since faced scant electoral competition in his nearly 22 years in office.

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