From Daily Kos:
Earlier this week, Rasmussen went into Minnesota and polled the public climate for the office-holders there. This was not covered in the wrap, because the three names involved (Al Franken, Amy Klobuchar, and Tim Pawlenty) are not on the ballot in the 2010 elections. What it did show that while Franken had net positives (41/31), they were less than both Klobuchar and the newly-minted right-winger Tim Pawlenty. This made its way into a variety of tradmed stories, but Jonathan Singer at MyDD made a great catch: Pawlenty's question was based on the traditional four-option menu of "strongly approve", "somewhat approve", "somewhat disapprove", "strongly disapprove". The Democrats were based on a four-option menu which asked if voters through their performance was "excellent", "good", "fair", or "poor". Research has shown that the former arrangement leads to better numbers in the top two boxes, because some voters will conflate a "fair" performance with one that is worthy of the rating "slightly approve". Not only that, but in a subtle wording change, it said Pawlenty was "doing a job" as governor, while it said Franken was "performing a role" as senator. When Mark Blumenthal went to Rasmussen Reports with a query about this, he was told it was a "mistake that slipped through the cracks."