Dak Prescott has run for 6 TDs in each of his first two seasons. Cam Newton once ran for at least 6 TDs in three straight seasons. In the Super Bowl era, who is the only other quarterback who has run for 6-plus touchdowns in back-to-back seasons? Hint: it's not one of the obvious type guys you might guess.
Tim Tebow, he ran for 6 TDs in both of his seasons with Denver (2010-11). There have been many other notable runners at this position – Michael Vick, Kordell Stewart, Steve Young, Randall Cunningham – but none of those guys scored 6 rushing touchdowns in back-to-back seasons.