Samford scored on a 2-yard touchdown run by Denzel Williams late in first half and a 55-yard interception return by Jamerson Blount with five minutes to play.
TCU piled up 555 total yards, including 200 by eight different rushers, while holding Samford to 143.
Samford defensive coordinator Bill D'Ottavio served as head coach in the absence of Pat Sullivan, who didn't travel while recovering from neck surgery.
Listenbee finished the game with three catches for 76 yards and two touchdowns.
TCU, coming off its first losing season since 2004, scored touchdowns on two of its first three possessions on a 2-yard run by B.J. Catalon and Listenbee's 38-yard catch.
Listenbee raced down the left sideline and beat James Bradberry in one-on-one coverage midway through the first quarter, diving for the ball near the goal line.
The touchdown pass to Porter immediately followed a TCU interception deep in Bulldogs territory. Ranthony Texada grabbed the ball in front of Gavin Sinclair near the right sideline, but the ball popped loose when Texada was hit. Paul Dawson caught it in midair and was tackled at the Samford 19.
Samford put together a 10-play, 75-yard drive capped by Williams running around right end for a touchdown with 3:30 remaining in the half. More than half of the Bulldogs' 143 total yards came on that possession.
Frogs kicker Jaden Oberkrom converted field goals of 22 and 25 yards.
TCU was led in rushing by Catalon with 38 yards on 10 carries.
The multi-talented Boykin moved from quarterback to receiver in 2013, starting the opener against LSU at that position. When senior quarterback Casey Pachall was sidelined with a broken non-passing arm in mid-September, Boykin made six starts at quarterback.
During the past week, TCU head coach Gary Patterson refused to say whether Boykin or Joeckel, a senior transfer, would start at quarterback. Joeckel joined the program in June after spending the past four years at Texas A&M, where he backed up Johnny Manziel for past two seasons and had one year of eligibility remaining.
Joeckel played the final nine minutes, throwing one touchdown and one interception.
TCU hasn't lost to a team from a lower division since the 27-24 overtime loss to Northwestern State in 2001, Patterson's first home game as head coach.
Sullivan was TCU's head coach 1992-97, and his '94 team won a share of the Southwest Conference championship. That team was honored at halftime, with about 50 players in attendance along with Sullivan's wife, Jean, and other family members.
Samford running back Krondis Larry was carried off the field after his left leg was tucked awkwardly during a tackle and didn't return to the game.
Frogs receiver Cameron Echols-Luper left the field during the fourth quarter on crutches.