Houston, Texas - Representatives Al Green and Christian Menefee are heading to a runoff race in the Democratic primary for Texas' 18th Congressional District.

According to CBS News, Menefee holds a narrow lead over Green, but neither candidate reached 50% of the vote, forcing a runoff in May.

78-year-old Green currently represents the Lone Star state's ninth district, but after mid-cycle redistricting by Republicans, he is now running to represent the 18th district.

This is Green's 12th re-election race, having first begun his time in Congress back in 2004.

He has repeatedly made headlines for his outspoken opposition to Donald Trump, and he has made multiple attempts to impeach the president.

37-year-old Menefee was only sworn into the House of Representatives in February after winning the special election to fill the seat of Sylvester Turner, who passed away last March after just two months in Congress.

The runoff election will be held on May 26.

Texas held a number of critical primary races on Tuesday, including two closely-watched Senate contests.

State Representative James Talarico secured the Democratic nomination over Congresswoman Jasmine Crockett, while Republicans John Cornyn and Ken Paxton are headed to a runoff.