-- As far as the men's Royal Rumbe match goes, if the winner of the Rumble is still getting a title shot at WrestleMania, then the likely winners of the match appear to be either Roman Reigns (Raw) or Shinsuke Nakamura or Randy Orton (Smackdown).
-- With Reigns, it's also possible that he doesn't win the Royal Rumble but gets his title shot against Brock Lesnar by winning the Elimination Chamber match.
-- Other names that were brought up in the past include Baron Corbin, who is now considered a longshot and John Cena, who almost surely won't win since he's not getting a title shot at WrestleMania.
Source: Wrestling Observer Newsletter. Subscription information & prices available at f4wonline.com