Tointon topped the scores after completing her third dance on Saturday night's show, but Stephenson was hot on her heels after picking up a perfect score of 40 for her quickstep.
Speaking about Tointon's rumba with pro Artem Chigvintsev, Alesha Dixon admitted that she had been moved emotionally by the dance.
"That was so touching Kara, and I could watch you all night," said the former champion. "Together you are mesmerising, and it's such a difficult dance. Technically you mastered it, emotionally you mastered it. For me, it was just pure magic."
Len Goodman joked: "Do me a favour, you're not supposed to dance that well!"
Meanwhile, Stephenson picked up the highest marks of the evening with Craig Revel Horwood describing her routine with James Jordan as "fabulous".
"I thought you did a fantastic interpretation of quickstep, and you're an inspiration for so many women. And for me that's what makes you a winner," added Dixon.
Gavin Henson remained bottom of the leaderboard after only picking up 31 points for his Viennese waltz. Scott Maslen and Matt Baker were tied in third spot after their three performances.
Two acts will leave Strictly tomorrow night. The results show airs at 7pm on BBC One.