The odds are high that the Duke and Duchess of Cambridge will choose a traditional royal name for their new-born son, according to bookmakers.
George has remained a firm favourite across Britain. Philip has also become a popular choice for the third-in-line to the throne's middle name, as both Charles and William have it and members of the royal family are often given multiple middle names. The Prince of Wales has four names, as does William.
A William Hill spokesperson said: “George was the second most popular name before we knew whether the baby would be a boy or girl, so now it moves into pole position and is the red hot favourite to be the name of the new Prince.”
Ladbrokes has Henry at 5/1, the same as it is offering George, after what it said was an “unprecedented amount of bets” in the last 48 hours, bringing it in from 50/1.
Spokeswoman Jessica Bridge said: “James is the red-hot favourite and the odds suggest we'll get the name on Tuesday. We're staring down the barrel of a gun if the baby's named Henry.”
Harry was the most popular first name for boys born in England and Wales in 2011, according to the Office for National Statistics. William and Kate could include a Harry or even Henry, Prince Harry's actual first name, as a middle name.
Henry, the given name of the Duke's brother Prince Harry, is also in the running, along with Alexander and Louis.
Midway through her pregnancy, Kate revealed she and William had a shortlist of names and that her friends were giving her ideas.
“We have a shortlist for both (boy and girl) but it's very difficult. My friends keep texting me names,” she told a well-wisher.
The baby, which will eventually be King, will be styled HRH Prince (forename) of Cambridge. Should he require a surname, such as on marriage, it will be Mountbatten-Windsor.
A spokesperson for Paddy Power said the top four names are George (7/4), James (4/1), Alexander (8/1) and Richard (10/1). The betting company reported 13,000 bets were placed after it was announced that the Duchess had given birth to a son on Monday afternoon.
He added: "We've seen most activity on George - as soon as it was announced that it was a boy it became the clear favourite. A couple of three figure bets have been placed on names, with one of the punters placing a £500 bet on George.
"Since it was announced the Royal baby was a boy last night we’v e seen over 13,000 individual bets totalling more than £50,000. There has been lots of activity since 8am this morning."
Video: Royal baby name guessing