The X Factor finalists will face the public vote for the first time tonight with show insiders promising "a twist" to the usual routine.
The first live show at 7.40pm will see the final 12 perform and the phonelines open for the public to deliver their verdict.
The pressure is on Katie Waissel after the bookmakers made her favourite to be booted off the ITV1 show.
The 24-year-old from Hertfordshire was widely seen as being put through the Judge's Houses stage by Cheryl Cole at the expense of fans' favourite Gamu Nhengu.
Cole has also come in for criticism and is tipped to speak out on tonight's show and defend her choices.
Waissel has vowed to prove the public wrong, saying: "I'm working really hard and being really positive and I can do it and I can't wait for the live shows to happen."
A show insider said there would also be a change to the usual format of the show which will "surprise" viewers.
The results will be announced on tomorrow's show when the finalists will be joined by last year's winner, Joe McElderry.
This weekend also sees the first contestant kicked off Strictly Come Dancing with magician Paul Daniels favourite for the chop.
All 14 couples will perform head to head tonight before the verdict is revealed on Sunday's 7.30pm show.