nobody knows how they came up with these numbers
dont take it too seriously as the real betting market hasn't moved today (yes, the people who actually bet real money)
Those of us old enough remember the betting markets went to the high 90s for Kerry in the middle of the day in 2004. I remember making a good chunk of pizza money day trading the Bush futures from around 10 or so back above 70 in only a few hours.
So history tells us the betting markets don't necessarily have better early information than anyone else does.