Political analyst Nate Silver writing in the New York Times:
Primary polls can be erratic, so the rule is not to get too worked up about any one set of numbers. But now there have been five surveys conducted since Rick Perry announced his presidential campaign — one each from Gallup, Rasmussen Reports and Public Policy Polling, and two from YouGov. Each shows Mr. Perry having vaulted into a lead over Mitt Romney.
On average, Mr. Perry gets 26 percent of the vote in the new surveys, as compared to 16 percent for Mr. Romney. By comparison, in polls conducted in the month prior to Mr. Perry’s announcement, he averaged 14 percent to Mr. Romney’s 21 percent.