The busty model, 34, first met Rylan when he appeared on her modelling show Signed By Katie last year, and they have kept in touch ever since.
Wearing a 'Team Rylan' t-shirt, Katie today told Daybreak viewers: "I'm supporting Rylan so watch The X Factor and support him tomorrow."
When asked if there was a chance of a duet (let's not forget she briefly dabbled in pop stardom back in 2010), Katie appeared to consider it.
"We'll do it in my lounge," she said. "I've got my karaoke set up, I'm a frustrated pop star aren't I, so we've done many duets in the lounge."
Presenter Kate Garraway then asked if Katie would perform with him on Daybreak.
"Do you know what, I will, but I'm better than Rylan. No, I'm only joking I'm not really," she added.
Katie is fast becoming Rylan's No1 fan. She has also showed her support by wearing a 'Rylan' onesie while having a sleepover with him at his X Factor hotel.
Do you think Rylan has what it takes to win The X Factor? Let us know in the comment box below.
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