Online bookies Betfair Sportsbook cut its odds on the name from 8/1 to 3/1 after a sudden flurry of bets on the Duke and Duchess of Cambridge's second child. Alice is a traditional royal name and is the middle name of Princess Anne and Prince Edward's daughter Lady Louise.
However, the last senior Royal to be given the moniker was Queen Victoria's second daughter Princess Alice.
Other girl names still in the running are Elizabeth at 5/1, Charlotte at 11/2 and Victoria at 12/1.
Betfair said that backing for a boy and girl had been fairly evenly split but a huge 85 per cent of people think the baby will be blonde.
Prince George, now 20 months, is fair, just like his dad at that age, despite Kate being a brunette. Cormac Dowling, Novelties and Politics Trader for Betfair, told the Mirror: "The public love a Royal announcement and we're expecting the arrival to be the novelty betting heat of the year.
"We're confident it may rival even the EastEnders Lucy Beale's killer market, which saw over £10 million of bets across the industry.
"Elizabeth had been the clear favourite until an unexpected rush of support for Alice over the last 24 hours and we've been forced to slash the price from 8/1 to 3/1."
Pregnant Kate will carry out her last official engagement this Friday (March 27) before going on maternity leave. She and Prince William will spend the day in south London visiting the Stephen Lawrence Centre in Deptford and another charity in Gypsy Hill.
ROYAL BABY ODDS
Royal Baby Name
Hair colour of baby
Gender of baby
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