#5 John Cena

One thing an experienced wrestling fan knows is that one can never count John Cena out of anything. He can win anything. Also with WWE's well-known penchant for having repeat Rumble match winners, this may not be as unlikely as it sounds.
With his part-time schedule and his mainstream attraction, WWE would be keen on giving him a marquee Wrestlemania match to wrestle, probably for the record of seventeen world titles. Winning the Royal Rumble match would give him the option of selecting a shot at either the WWE or the Universal Championship by virtue of his free agent special status.
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This can lead to weeks of speculation after which he can go for either Bryan, Brock, or preferably Braun presuming he would conquer the Beast on the same night and become the new Universal Champion. After this, having Braun go over John at Wrestlemania would cement his place at the top of the mountain.
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