Prediction Markets Update (September 20, 2008)

The state-by-state contracts continue to imply that Mr. Obama currently holds a 273-227 “lead” over Mr. McCain (based upon my cutoff price point of 55 for allocating Electoral College votes). The “swing” states continue to include Nevada (5 Electoral College votes), Ohio (20 Electoral College votes), and Virginia (13 Electoral College votes).

The 2008.PRES.OBAMA Intrade contract now trades at 50.8, whereas the 2008.PRES.McCAIN Intrade contract is currently trading at 46.1 (compared with 50.5 and 47.8 respectively as reported on yesterday’s update).

Over at FiveThirtyEight.com, Mr. Obama has now opened up a 306.5 to 231.5 advantage over Mr. McCain. The Gallup Daily Tracking poll is also generating numbers that are not inconsistent with what we are finding here; today, Mr. Obama’s lead of 6 points is the largest that it has been since before the two parties’ conventions in late August and early September.

Addendum: September 20, 2008 Electoral College Vote allocation

Barack Obama (273): California (55), Colorado (9), Connecticut (7), Delaware (3), District of Columbia (3), Hawaii (4), Illinois (21), Iowa (7), Maine (4), Maryland (10), Massachusetts (12), Michigan (17), Minnesota (10), New Hampshire (4), New Jersey (15), New Mexico (5), New York (31), Oregon (7), Pennsylvania (21), Rhode Island (4), Vermont (3), Washington (11), and Wisconsin (10)

John McCain (227): Alabama (9), Alaska (3), Arizona (10), Arkansas (6), Florida (27), Georgia (15), Idaho (4), Indiana (11), Kansas (6), Kentucky (8), Louisiana (9), Mississippi (6), Missouri (11), Montana (3), Nebraska (5), North Carolina (15), North Dakota (3), Oklahoma (7), South Carolina (8), South Dakota (3), Tennessee (11), Texas (34), Utah (5), West Virginia (5), and Wyoming (3)