February 13, 2016

Why the big shift in the polls?

Much of the movement in the Marquette University Law School poll from last month to this month comes among independents. In August those not belonging to any political party preferred Republican Tommy Thompson over Democratic Tammy Baldwin in the US Senate race, 50-41 percent. That 9-point lead reversed this month, putting Baldwin ahead by exactly the same lead Thompson had — an 18-point shift.

Poll Director Charles Franklin says, “Independents are the group that clearly showed the greatest shift.”

The presidential race looks a lot like the US Senate race. Independents are largely responsible for giving Democratic President Obama a 14-point lead over Republican challenger Mitt Romney in Wisconsin.

“Independents have shifted from a 2-point Obama margin in August to a much bigger 53-38 margin in September,” says Franklin.

The political science professor says the change in results is a combination of advertising, national conventions, newspapers, social media, and a “whole host of things.” Franklin says there are “many chances to observe and absorb” the goings on in the political campaigns.

And if you don’t like the results … “As we’ve said all year, don’t rely on one poll, even if it’s ours; make sure you look at all of the polling that’s available.”

Some critics complained about the political makeup of the poll. Franklin says the “September poll makeup is about two points more Democratic and three points less Republican than average, which is within the margin of error.” Independents were 37 percent of the September sample, no change for the year.

If the sample were adjusted to match the yearlong average partisan makeup, both margins would tighten, with Baldwin leading Thompson 48 to 43 percent and Obama leading 51 to 43 percent.

AUDIO: Jackie Johnson report 1:50

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