U.S. Rep. Christian Menefee defeated U.S. Rep. Al Green on Tuesday in the Democratic runoff for Houston's newly redrawn 18th Congressional District. Why it matters: Menefee's victory is set to end Green's two-decade run in Congress. State of play: Menefee received 68.6% (21,678 votes), while Green received 31.4% (9,930 votes) with 61% of votes counted, per the Associated Press . The AP called the election in favor of Menefee about 30 minutes after polls closed Tuesday. The two were the top vote-getters in the March Democratic primary, but neither won enough support to avoid a runoff. Catch up quick: Menefee already won a special election earlier this year to fill the seat left vacant by former Rep. Sylvester Turner's death . Menefee had to run again to keep the seat for the term starting in 2027. Green represented Houston's 9th Congressional District for two decades before running in the 18th after Texas lawmakers redrew his old seat to favor Republicans.…