Campbell, who stands 6-foot-7 and weighs 310 pounds, said he has been told he could be drafted from the middle of the first round to the middle of the second.
"I feel I can be something special and this is best for me," Campbell said. "I have good size and I can protect the quarterbacks' blind side. I played defensive line in high school so I can also think like a defensive player, which is an advantage."
Scouts Inc. rates Campbell as the No. 24 prospect for the 2010 draft.
Maryland does not play in a bowl game, so Campbell can begin his training soon, likely in Miami.
Joe Schad covers college football for ESPN.