With the ground currently described as soft at Ascot and the forecast unsettled for the week ahead, last year's winner Highland Reel, who needs top of the ground to be seen at his best, drifted a little in the market from 13-8 to 15-8 with Coral.
Trained by John Gosden, Enable, who had seemed likely to head towards the Yorkshire Oaks at York next month, is now on the verge of taking part just two weeks after a classy performance in the Irish Oaks at the Curragh.
The Khalid Abdullah-owned filly was cut to 7-4 from 15-8 with Coral after Gosden indicated a final decision would be made on Wednesday.
Coral spokesman David Stevens said: "John Gosden won the King George with the Oaks-winning Taghrooda three years ago, and with Enable very much in the running to replicate that success, we make her favourite to beat the older colts, with the weight allowance in her favour and some top-class form to her name."
As benefited Taghrooda, Enable will have a sex and weight allowance meaning she will be in receipt of a stone from the older males.
"She's been left in the race and the final decision will be made on Wednesday when I discuss matters with the owner," said Gosden.
"Apart from a cut on her leg, which has healed, she came out of the Irish Oaks very well. She's had plenty of time between her previous races. It's not like she's been over-raced this season. She's fresh and very well.
"Frankie (Dettori) got a great feel off her at the Curragh and was pretty excited talking about her afterwards coming home on the plane.
"He (Dettori) has to shed some weight himself if we are going to do this, but I've got to make it clear I need to talk to the owner."
Gosden confirmed Jack Hobbs, who disappointed in the Prince of Wales's Stakes at Royal Ascot, having previously won the Dubai Sheema Classic in such style, as an intended starter.
The trainer told At The Races: "We always wanted to run Jack Hobbs in the Prince of Wales's, but the fact it turned out to be the hottest June day for 40 years and the ground lightning fast was entirely the wrong thing for him.
"Obviously he's got no problem with a mile and a quarter. He's run brilliantly twice in autumn ground there, but a mile and a half with cut in the ground is right up his street."
The Gosden pair, and likely pacemaker and stablemate Maverick Wave, are among 16 remaining contenders for the King George.
They are joined by the Aidan O'Brien-trained brothers, last year's winner Highland Reel and Hardwicke hero Idaho.
O'Brien has also left in Johannes Vermeer and US Army Ranger.
Charlie Appleby can call on Hawkbill and Frontiersman, who fought out a finish at Newmarket recently, while David Simcock is another with two possibles in Algometer and Desert Encounter.
Eclipse winner Ulysses will aim to give Sir Michael Stoute a record sixth triumph in a race he last claimed seven years ago with Harbinger, but he has taken out Dartmouth.
Dante one-two Permian and Benbatl, who both went on to win at Royal Ascot, are in the mix, as are My Dream Boat and Argentinian challenger Sixties Song.