Westlife's duet with Diana Ross is the favourite to be number one at Christmas according to a leading bookmaker.
Westlife are at number two in the single and album charts
Paddy Power tips the Irish boy band for the top spot, with the as yet unnamed winner of the ITV1 talent show as their second favourite.
Ladbroke has the X Factor winner and Westlife as joint favourites.
William Hill says 20-year-old Mancunian Shayne Ward will win X Factor and is 11/4 favourite for the Yuletide crown, last year won by Band Aid 20.
Viewers on Saturday night saw pop hopeful Maria Lawson voted off the programme by judge Louis Walsh.
The decision left William Hill reeling, having originally made the 30-year-old Londoner a 66/1 outsider to leave the programme.
Maria Lawson was voted off The X Factor on Saturday
"Sixty-six to one was completely the wrong price for Maria to leave the show, so we got completely hammered," said spokesman Rupert Adams.
William Hill now has Ward as 6/5 favourite to win the show, with 41-year-old Londoner Andy Abraham at 10/3.
BBC One's Strictly Come Dancing was the ratings winner on Saturday night, with 9.1 million watching compared with The X Factor's 8.5 million.
The ballroom dancing show was broadcast immediately after a live version of Match of the Day.
However, 8.2 million saw the X Factor results programme later in the evening, compared with 8 million for the Strictly Come Dancing equivalent.