I always wondered how pollster determine who is a "likely Voter" when only about 36% ( +-2%) in a mid-term elections turn out to vote.
So if polling and turn out are porportional, then for every 100 phone calls that are answered, only 36 callers will vote, and that's IF only potential voters are the only ones that answers the poll's phone call.
Mid-term election U.S. turn out statistics: 1994, 36%; 1998, 35%; 2002, 36%
Which means that to get 625 "likely voters," they'd have had to have called, what, 1800 people? Right.