Heading into the debates, President Obama maintains a striking lead over Mitt Romney in the prediction markets and Nate Silver's proprietary forecast.

We're tracking three sources of "odds" on the US Presidential election:

Nate Silver's aggregate poll forecast

Intrade's prediction market

Betfair's prediction market

President Obama's odds of winning the election have surged to new highs on Nate Silver's measures and slumped in the past week on Intrade.

First, Nate Silver of the New York Times currently gives Obama a 86% chance of reelection. That's an all-time peak.

On Intrade, meanwhile, Obama's odds surged to nearly 80% after video surfaced of Mitt Romney dissing half the country in remarks at a private fundraiser, but they have since slumped to 75%.

And, on Betfair, Obama's odds have continued to trend higher and are now just over 80%: