Hopefuls on the ITV reality pop show last night (November 20) performed songs by the Fab Four following the historic digital release of the band's catalogue on iTunes.
And John Lennon's widow took to Twitter to support two of the frontrunners in the competition's girls category.
Show favourite Cher Lloyd performed 'Imagine' while the embattled Katie Waissel tackled 'Help'.
Following the show, Ono tweeted: "Cher & Katie - I watched you sing Imagine and Help! on #XFactor and thought you were fantastic! A big hug to both of you, love yoko." (sic)
This was the first time The X Factor has staged a Beatles night, although Paul McCartney performed at the final of last year's competition.
The band's songs have been tipped to re-enter the charts tonight.
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