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Behind the Numbers
Posted at 12:44 PM ET, 03/25/2009

Contradictory Pennsylvania Senate Results All in the Technique

Two new polls out today show Pennsylvania Republican Senator Arlen Specter may or may not be leading his 2004 primary opponent Pat Toomey, should Toomey return for a rematch. A Quinnipiac University poll out this morning says Toomey has the edge over Specter, 41 percent to 27 percent, with 28 percent undecided, while today's release from Franklin and Marshall finds Specter at 33 percent with Toomey at 18 percent and 42 percent undecided.

The seemingly contradictory results offer a great example of the impact question wording can have on a poll's result. The two surveys offer a similar read on Specter's standing in the hypothetical contest: about three in 10 registered Republicans said they would vote for him in both polls. Specter is the better known figure and, as the incumbent, the one on whom voters are passing judgment at this early stage, so it makes sense that his standing would hold steady across polls.

The variation is all on Toomey's side of the coin. Despite his prior run for Specter's seat, Toomey is largely an unknown quantity - nearly three-quarters of Republicans in the Quinnipiac poll said they hadn't heard enough about him to have an opinion - suggesting his support in the two polls is driven more by question wording than strong sentiment for or against his candidacy.

Quinnipiac's poll asks voters, "If the 2010 Republican primary for United States senator were being held today and the candidates were Arlen Specter and Pat Toomey, for whom would you vote?"

Franklin and Marshall's question starts off about the same, but watch the big finish, "If the 2010 Republican primary election for U.S. senator were being held today and the candidates included Arlen Specter, Pat Toomey, and Peg Luksik, would you vote for Arlen Specter, Pat Toomey, Peg Luksik, some other candidate, or aren't you sure how you would vote?"

That final phrase makes all the difference. Quinnipiac's poll offers voters what we in polling call a forced choice, mimicking the one they would face in the voting booth (unlike Nevada, Pennsylvania does not allow voters to cast a ballot for "none of these candidates"), and as such is a great measure for predicting voter behavior. Franklin and Marshall's question makes it easier for voters to say they haven't made up their minds, a perfectly valid response more than a year before anyone has to cast a ballot.

Beyond the horse race, a more important finding common to both polls portends bad news for Specter. More than half (53 percent in the Quinnipiac poll, 51 percent in the F&M survey) of Republicans said the state's senior senator does not deserve reelection.

By Jennifer Agiesta  |  12:44 PM ET, 03/25/2009

Categories:  Congress, Congress

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