David Strömberg, writing over at Vox EU, observes:
Without the Bradley effect, Obama has an 84% chance of winning, receiving 52% of the two-party vote share. (Obama is expected to receive 52% even though he is polling at 53% of the two-party vote share, because of the catch-up effect.) However, the race is a coin flip if the presidential race will exhibit a Bradley effect of the same size as the average for the 22 House, Senate and Governor races 1998-2006 for which I have data. Obama’s win probability drops to 53%, with an expected vote share of 49.9
Bugger me, that’s depressing. Transcend, dammit, transcend!