Parris Campbell – He committed on the spot to Ohio State once an offer was issued. Campbell is still adding bulk and I think he will be the typical running back, and not a slot back, Percy Harvin type.
I think Ohio State is done at the position due to a lack of space in the class and having the cupboard pretty full in the backfield already. One could always sneak in near the end depending on what the numbers look like and what other prospects the coaching staff is in on.
Havelock, North Carolina running back Derrell Scott would seem to fit the Ohio State offense like a glove. He has a lot of versatility and could serve the slot-back role well with his ability to play in the slot and be a receiver as well. The Buckeyes are in his top three, along with Florida State and South Carolina, and are expected to have him on campus in June.
Joe Mixon is more of a traditional running back at 6-foot and around 200 pounds. Ohio State is getting a similar player in Parris Campbell so there isn't a need for what Mixon brings to the table. Assuming they could make the numbers work, Mixon falls under the category of being too good to pass up.
The second group is stocked with athletes that fill a role identical to the aforementioned Derrell Scott. I think the Ohio State staff would see them a step below Scott but certainly candidates to be in the class.
The only player of the three to set foot on Ohio State's campus so far is Donte Williams. Hilliman plans to check out the Buckeyes' campus, as does Haden. With players ahead of them on the board and the scholarship situation being what it is, it is difficult to foresee a situation where it got serious between either of the three and the Ohio State staff.
All three of the last sets of running backs have been offered by Ohio State but it is very unlikely they end up in the Buckeyes' class. Gresham is already committed to Texas, while the other two have shown little interest in Ohio State lately.