#2 Charlotte Flair

While the men's Royal Rumble has many possible candidates for the iron man role, the women's match doesn't. There are only two women who can pull off the role.
One of them is Bayley, but given how she has been booked the last year, it is highly unlikely she will do anything of that sort.
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She was barely used in last year's Rumble match and probably will be used scarcely this year as well. Thus, the only possible iron man for the Women's Rumble match is Charlotte Flair.
Charlotte has built a legacy for herself which no other woman on the roster can match. She is the women's division's biggest star. Also, she is one of the favorites to win the Rumble match.
But given that Becky Lynch is the odds on favorite, it is unlikely Charlotte wins as the internet odds are rarely wrong. So it should be a given certainty that Charlotte enters early in the match and lasts all the way to the end.
She more or less has to pull off an iron man performance as there is no other woman fit enough to do it.
Charlotte might win the match but it is more likely that she plays the iron man before being eliminated by Becky Lynch.
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