Sam Bailey looks on course to claim the first X Factor Christmas No 1 for three years, but her sales are only a quarter of those achieved at this stage by the 2012 victor.

Sam has shifted nearly 45,000 downloads of her first single Skyscraper after her triumph on the ITV show on Sunday.

Previous winner James Arthur sold a colossal 187,000 copies of his single Impossible during his first full day on sale.

James’s track proved to be the fastest seller of any X Factor winner, but other past stars from the talent show have amassed much bigger sales. Alexandra Burke’s debut Hallelujah sold 147,000 in 2008, Matt Cardle’s When We Collide sold 112,000 in 2010 and Little Mix sold 69,000 during the same time period.

Sam’s track has not even matched the first day’s sales for Shayne Ward’s That’s My Goal in 2005 which achieved 46,000 sales by midnight on Monday, and that was when the popularity of downloads was still taking off with CDs still the main format. It went on to sell 742,000 copies by the weekend including all formats.

Today’s sales figures, compiled by the Official Charts Company, show Sam is still way out in front in the race for the Christmas No 1 which will be announced on Sunday, December 22. She is 27,000 copies ahead of her nearest rival, Happy by Pharrell Williams, which is from the Despicable Me 2 soundtrack.

The chart firm’s chief executive Martin Talbot said: “Sam Bailey is out of the blocks and into a strong lead in the race to become this year’s Official Christmas No 1.”

Another past X Factor star, Leona Lewis, is at number three with One More Sleep, according to early sales reports.

Sam’s single comes out on CD on Wednesday (December 18) and her sales are expected to pick up as the 36-year-old is thought to appeal to a more mature audience who may be less likely to buy downloads.

The last winner of the series to achieve a Christmas No 1 was Matt Cardle in 2010. A backlash against the programme from music fans has sometimes been responsible for denying the winner the festive top spot.

In 2009 Joe McElderry missed out because of a campaign to get Rage Against The Machine to the top instead generating huge sales. Efforts to repeat the feat this year by propelling AC/DC’s Highway To Hell are failing to match it, the song being at number four so far with around 13,000 sales.

However, it could still prove to be the rock band’s first top 10 hit in a four-decade career.