Political polls conducted by Pulse Opinion Research and released by Rasmussen Reports have been identified in the past as showing better results for Republican candidates than other polling houses.

In its latest pollster ratings, FiveThirtyEight.com scored Rasmussen/Pulse Opinion Research's bias at 2.3 points to the Republican side based on 623 polls analyzed. That's one of the heaviest leans of the hundreds of polling organizations that the Nate Silver-directed site ranked.

So when Rasmussen released a poll on Wednesday showing Democratic challenger Mary Burke leading Republican Gov. Scott Walker 49 percent to 48 percent among likely voters in the Wisconsin gubernatorial race, Burke's actual advantage could have been interpreted as being larger.

That's what the poll-averaging model created for the Cap Times by UW-Madison doctoral candidate Brad Jones showed.