Dubious Gallup polls

The latest Gallup polls, which gave Bush a large lead, have ridiculously biased polling samples (from Atrios).

Likely Voter Sample Party IDs – Poll of September 13-15
Reflected Bush Winning by 55%-42%

Total Sample: 767
GOP: 305 (40%)
Dem: 253 (33%)
Ind: 208 (28%)

Registered Voter Sample Party IDs – Same Poll
Reflected Bush Winning by 52%-44%

Total Sample: 1022
GOP: 381 (38%)
Dem: 336 (33%)
Ind: 298 (30%)

For context, in the 2000 elections the voters were 39% Democrats, 35% Republicans and 26% Independents. Democrats comprised 4% more of the voters than Republicans did, while in the Gallup polls they were 5% or 7% less. And considering current attitudes towards Bush, it seems likely that the 2004 voters will be even more Democratic.