The 30-year-old star has been winning the nation's hearts while starring on the ITV show and has made it all the way to the final.
And Mark, who has written two books on publicity stunts and has won several awards for his work, believes it is because Jordan is "genuinely being himself".
Jordan has been a favourite with the bookies for days now and the PR genius is sure Jordan will continue to shine.
Speaking to Daily Star Online on what is behind Jordan's success on the show, Mark said: "Being a Radio 1 DJ he has quite a good young fan base.
"Secondly, the focus is always on the more well known. But when someone comes out of the blue who is unknown, like Scarlett Moffatt , but is who they are and those things like throw up on the first day, it's the vulnerability and authentic vulnerability generates a lot of interest."
And Jordan has certainly done that as he tragically threw up during the first trial and despite his fears, has carried out every trial he has been up for.
On how much money Jordan could make from the show Mark said it depends if he wins - but he will likely be a millionaire within a year.
Mark said: "It depends if he wins, if he wins and gets a good agent he will easily make a million or more."
The author continued: "He could easily exploit a million quid out of endorsements."
Mark also said that despite Covid-19 he doesn't believe it will affect too much what the stars earn after due to online campaigns and endorsements.
On what he thinks of the cast this year, Mark said: "You have to credit the production team. The casting has been particularly good this year.
"Vernon Kay, Shane Richie, Coronation Street stars and more, you got the eye-candy in there and disability as well. All the boxes have been ticked off for modern TV."
It's no surprise that stars can earn megabucks after leaving the jungle.
Emily Atack is just one of the stars who went on to earn half a million after the show thanks to her sketch show and stand up tour.
The 30-year-old comedian, who first rose to fame starring in The Inbetweeners, has cashed in on £500k since she left the jungle and is possible for her to make a million as her tour, The Emily Atack Show, is soon to start.
The I'm a Celebrity... Get Me Out of Here! final airs tonight on ITV at 9pm