Sample sizes determining the proportion of voters supporting a presidential candidate in a US election are generally even smaller ( < 3000 ). But that's still l

Sample sizes determining the proportion of voters supporting a presidential candidate in a US election are generally even smaller ( < 3000 ). But that's still large enough to predict an election with decent accuracy. http://stats.stackexchange.com/questions/166/how-do-you-decide-the-sample-size-when-polling-a-large-population http://stats.stackexchange.com/questions/166/how-do-you-deci... http://www.pollingreport.com/ncpp.htm http://www.pollingreport.com/ncpp.htm