Horton, a junior out of Atlanta (Ga.) Lakeside traveled to Durham Saturday morning and the offer came before Duke hosted Miami.
"I had a long talk with offensive line coach John Latina and we talked about a lot of different things," said Horton.
"Coach Latina talked about their interest in me, how things are going there, and we just tried to build on our relationship. During our conversation, he talked about how he wanted me there and offered me."
After the offer was extended, Duke took care of business on the field with a 48-30 win over the Hurricanes.
The 6-foot-4, 310 pound offensive lineman liked what he saw all day in Durham.
"I think Duke is starting to get a lot of respect now. It was a great game, they showed they can compete with top teams, and Duke is looking like it will compete for a big bowl game.
"I liked the game, I loved the campus, and I think the coaches are great there. I love how everyone pays close attention to details there. It is a great school."
He does not have a leader at this time.
"I have not even thought about favorites yet," said Horton. "I am looking at all the schools the same right now. I liked what I saw at Duke and it would be high my list, but no favorites for me right now."
Horton plans on visiting Georgia Saturday.