#3 Rusev
Rusev debuted for WWE in 2013 and would dominate in NXT. At the Royal Rumble in 2014, he made his main roster debut. Since then his career has progressed steadily, until recently. At present Rusev's popularity is soaring.
Every week Rusev and Aiden English received immense cheers, see the video below. Together they have created Rusev Day. It is impossible to watch an event without seeing their merchandise.
In recent months chants of Rusev Day have dominated areas around North America. Moreover, Rusev continues to perform in excellent matches. Most notably he faced off against AJ Styles. This match cemented Rusev's position to challenge for the WWE Championship. It just depends on when WWE wish to pull the trigger.
When will Rusev become WWE Champion?