There are many reasons political polls can go awry and give a wrong picture of where a candidate stands during an election, such as the errors made in predicting House Majority Leader Eric Cantor's re-election chances, according to Chris Wilson, partner for WPA Opinion Research.
"It's been a tough week for our profession on several levels," Wilson told "America's Forum" host J.D. Hayworth on Friday's Newsmax TV program, noting that on average, one out of every 20 polls can have errors that can give an incorrect reading on where a candidate or issue stands.
"If you think a poll is wrong, you should redo it," said Wilson. "It absolutely happens."
But the difference between a "good pollster" and a "polling factory" is that a good pollster doesn't just pump out numbers, but analyzes them," he said.
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For example, Wilson explained, his company once did a poll on day seven of the NBA Finals, and discovered its candidate had dropped by several points. As it turned out, samples of men aged 35 and older were off because "none of them were going to talk to us on the night of the NBA Finals."
But Wilson defended Cantor's pollster, veteran Republican John McLaughin, who less than a week before the Virginia primary released an internal poll showing Cantor ahead of college professor David Brat by 34 points.
"I worked for John and he's one of the smartest in the country," Wilson said. "John is very attentive to his races. My bet is, he's gone back and looked at this, but it's not really something you can talk about after the fact."
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