Actually, there probably is only one guy with a shot at 4 stars and that is Manning - if you follow Rivals rankings. And I have no idea if Manning is a guy that will go up or down - haven't followed him that closely.
Anybody that has already been evaluated - well they move, but the later you get the less movement there is. Remember, these are "recruiting projections" and are based a lot on frame, speed, potential, etc., in addition to performance - not unlike what goes on with the NFL draft.
Maybe Russo has a shot, but I doubt it. You look at his "combine" numbers and they are awfully low. Maybe he is a 4* for the RU system, but that doesn't mean he will be rated a 4 star by Rivals - there will be kids that are athletically off the charts ahead of him that need more development with their skill set. I would bet he ends up 5.7 3* - which historically is still a very good recruit - not a lot of difference in success rates between the 5.7s and the 4 stars.
Of course plenty of RU fans will ignore all of the above and whine that Rivals and Farrell and Friedman have a bias against RU. Just like every other fan base in the country is absolutely sure of. It's comical if you go on other sites, everyone says the same da&n thing. They should just make everyone happy and give everyone 4*s.